pickleとjsonモジュール
212137 ワード
jsonモジュール
jsonモジュールはシーケンス化と逆シーケンス化を実現し、主なユーザーの異なるプログラム間のデータ交換をまず見てみましょう.
dumps()シーケンス化
以上から分かるように、dumpsは実はシーケンス化されたインスタンスを生成し、この後dumpと区別され、漢字が英語ではなくバイトコードに変換される.
loads()逆シーケンス化
上記dumps()とloads()のシーケンス化と逆シーケンス化は、プログラム間で相互作用する、すなわちファイルを通過せず、jsonのみである.dumps()はインスタンスをシーケンス化し、その後jsonを受信する.loads()は逆シーケンス化され,プログラム間のインタラクションが順次実現される.では、ファイルでどのように対話しますか?
ファイル内のインタラクション:
上記のコードでは、シーケンス化されたインスタンスをファイルに書き込み、jsonを使用します.dumps()生成例,fw.write()ファイルに書き込むには、ファイルのwrite()で書き込む必要があります.
ファイルの逆シーケンス化:
上のファイルの逆シーケンス化では、まずファイルの内容を読み出し、write()を使用して書き込まれるのでread()を出てから逆シーケンス化してインスタンスを生成します.
次にload()とdump()のシーケンス化と逆シーケンス化を見てみましょう.
dump()シーケンス化
上から見えますjsondump()は、インスタンス化された情報を直接指定ファイルにシーケンス化し、write()を必要とせず、直接自分で書き込むことができますが、dumps()はシーケンス化されたインスタンスにすぎず、自分でwrite()をファイルに追加する必要があります.
load()逆シーケンス化
load()逆シーケンス化は読み取り後に逆シーケンス化する必要はありません.dump()に入っているので、ファイルから直接逆シーケンス化できます.
まとめ:
上記のdumps()、loads()およびdump()、load()のシーケンス化および逆シーケンス化から、dumps()はシーケンス化によって生成されたインスタンスであり、loads()は読み書きされたインスタンスであり、dumps()およびloads()は主に異なるプログラムまたはインタフェース間のデータ交換伝送に用いられ、dump()およびload()はファイルレベル間の読み取りおよび書き込みに適しており、両者の間には重点がある.
これは両者の機能が同じで、使い方が違うというわけではありませんが、実際に設計するときに方向を重視するのは違います.
jsonソースコード
pickleソースコード
転載先:https://www.cnblogs.com/gengcx/p/7331120.html
jsonモジュールはシーケンス化と逆シーケンス化を実現し、主なユーザーの異なるプログラム間のデータ交換をまず見てみましょう.
dumps()シーケンス化
import json
'''json '''
users = ["alex","tom","wupeiqi","sb"," "]
mes = json.dumps(users) # ，
print(mes)
：
["alex", "tom", "wupeiqi", "sb", "\u803f\u957f\u5b66"]以上から分かるように、dumpsは実はシーケンス化されたインスタンスを生成し、この後dumpと区別され、漢字が英語ではなくバイトコードに変換される.
loads()逆シーケンス化
import json
'''json '''
users = ["alex","tom","wupeiqi","sb"," "]
mes = json.dumps(users) # ，
print(" :",mes)
data = json.loads(mes)
print(" ：",data)
：
: ["alex", "tom", "wupeiqi", "sb", "\u803f\u957f\u5b66"]
： ['alex', 'tom', 'wupeiqi', 'sb', ' ']上記dumps()とloads()のシーケンス化と逆シーケンス化は、プログラム間で相互作用する、すなわちファイルを通過せず、jsonのみである.dumps()はインスタンスをシーケンス化し、その後jsonを受信する.loads()は逆シーケンス化され,プログラム間のインタラクションが順次実現される.では、ファイルでどのように対話しますか?
ファイル内のインタラクション:
import json
'''json '''
users = ["alex","tom","wupeiqi","sb"," "]
mes = json.dumps(users) # ，
''' mes '''
with open("users",'w+') as fw:
fw.write(mes)上記のコードでは、シーケンス化されたインスタンスをファイルに書き込み、jsonを使用します.dumps()生成例,fw.write()ファイルに書き込むには、ファイルのwrite()で書き込む必要があります.
ファイルの逆シーケンス化:
import json
with open('users','r+') as fr:
mess = json.loads(fr.read())
print(mess)
：
['alex', 'tom', 'wupeiqi', 'sb', ' ']上のファイルの逆シーケンス化では、まずファイルの内容を読み出し、write()を使用して書き込まれるのでread()を出てから逆シーケンス化してインスタンスを生成します.
次にload()とdump()のシーケンス化と逆シーケンス化を見てみましょう.
dump()シーケンス化
import json
users = {"alex":"sb","wupeiqi":666," ":6969}
with open("users","w+") as fw:
json.dump(users,fw)上から見えますjsondump()は、インスタンス化された情報を直接指定ファイルにシーケンス化し、write()を必要とせず、直接自分で書き込むことができますが、dumps()はシーケンス化されたインスタンスにすぎず、自分でwrite()をファイルに追加する必要があります.
load()逆シーケンス化
import json
with open('users','r+') as fr:
users = json.load(fr)
print(users)
：
{'alex': 'sb', ' ': 6969, 'wupeiqi': 666}load()逆シーケンス化は読み取り後に逆シーケンス化する必要はありません.dump()に入っているので、ファイルから直接逆シーケンス化できます.
まとめ:
上記のdumps()、loads()およびdump()、load()のシーケンス化および逆シーケンス化から、dumps()はシーケンス化によって生成されたインスタンスであり、loads()は読み書きされたインスタンスであり、dumps()およびloads()は主に異なるプログラムまたはインタフェース間のデータ交換伝送に用いられ、dump()およびload()はファイルレベル間の読み取りおよび書き込みに適しており、両者の間には重点がある.
これは両者の機能が同じで、使い方が違うというわけではありませんが、実際に設計するときに方向を重視するのは違います.
jsonソースコード
r"""JSON (JavaScript Object Notation) is a subset of
JavaScript syntax (ECMA-262 3rd edition) used as a lightweight data
interchange format.
:mod:`json` exposes an API familiar to users of the standard library
:mod:`marshal` and :mod:`pickle` modules. It is derived from a
version of the externally maintained simplejson library.
Encoding basic Python object hierarchies::
>>> import json
>>> json.dumps(['foo', {'bar': ('baz', None, 1.0, 2)}])
'["foo", {"bar": ["baz", null, 1.0, 2]}]'
>>> print(json.dumps("\"foo\bar"))
"\"foo\bar"
>>> print(json.dumps('\u1234'))
"\u1234"
>>> print(json.dumps('\\'))
"\\"
>>> print(json.dumps({"c": 0, "b": 0, "a": 0}, sort_keys=True))
{"a": 0, "b": 0, "c": 0}
>>> from io import StringIO
>>> io = StringIO()
>>> json.dump(['streaming API'], io)
>>> io.getvalue()
'["streaming API"]'
Compact encoding::
>>> import json
>>> from collections import OrderedDict
>>> mydict = OrderedDict([('4', 5), ('6', 7)])
>>> json.dumps([1,2,3,mydict], separators=(',', ':'))
'[1,2,3,{"4":5,"6":7}]'
Pretty printing::
>>> import json
>>> print(json.dumps({'4': 5, '6': 7}, sort_keys=True, indent=4))
{
"4": 5,
"6": 7
}
Decoding JSON::
>>> import json
>>> obj = ['foo', {'bar': ['baz', None, 1.0, 2]}]
>>> json.loads('["foo", {"bar":["baz", null, 1.0, 2]}]') == obj
True
>>> json.loads('"\\"foo\\bar"') == '"foo\x08ar'
True
>>> from io import StringIO
>>> io = StringIO('["streaming API"]')
>>> json.load(io)[0] == 'streaming API'
True
Specializing JSON object decoding::
>>> import json
>>> def as_complex(dct):
... if '__complex__' in dct:
... return complex(dct['real'], dct['imag'])
... return dct
...
>>> json.loads('{"__complex__": true, "real": 1, "imag": 2}',
... object_hook=as_complex)
(1+2j)
>>> from decimal import Decimal
>>> json.loads('1.1', parse_float=Decimal) == Decimal('1.1')
True
Specializing JSON object encoding::
>>> import json
>>> def encode_complex(obj):
... if isinstance(obj, complex):
... return [obj.real, obj.imag]
... raise TypeError(repr(o) + " is not JSON serializable")
...
>>> json.dumps(2 + 1j, default=encode_complex)
'[2.0, 1.0]'
>>> json.JSONEncoder(default=encode_complex).encode(2 + 1j)
'[2.0, 1.0]'
>>> ''.join(json.JSONEncoder(default=encode_complex).iterencode(2 + 1j))
'[2.0, 1.0]'
Using json.tool from the shell to validate and pretty-print::
$ echo '{"json":"obj"}' | python -m json.tool
{
"json": "obj"
}
$ echo '{ 1.2:3.4}' | python -m json.tool
Expecting property name enclosed in double quotes: line 1 column 3 (char 2)
"""
__version__ = '2.0.9'
__all__ = [
'dump', 'dumps', 'load', 'loads',
'JSONDecoder', 'JSONDecodeError', 'JSONEncoder',
]
__author__ = 'Bob Ippolito pickleソースコード
"""Create portable serialized representations of Python objects.
See module copyreg for a mechanism for registering custom picklers.
See module pickletools source for extensive comments.
Classes:
Pickler
Unpickler
Functions:
dump(object, file)
dumps(object) -> string
load(file) -> object
loads(string) -> object
Misc variables:
__version__
format_version
compatible_formats
"""
from types import FunctionType
from copyreg import dispatch_table
from copyreg import _extension_registry, _inverted_registry, _extension_cache
from itertools import islice
import sys
from sys import maxsize
from struct import pack, unpack
import re
import io
import codecs
import _compat_pickle
__all__ = ["PickleError", "PicklingError", "UnpicklingError", "Pickler",
"Unpickler", "dump", "dumps", "load", "loads"]
# Shortcut for use in isinstance testing
bytes_types = (bytes, bytearray)
# These are purely informational; no code uses these.
format_version = "4.0" # File format version we write
compatible_formats = ["1.0", # Original protocol 0
"1.1", # Protocol 0 with INST added
"1.2", # Original protocol 1
"1.3", # Protocol 1 with BINFLOAT added
"2.0", # Protocol 2
"3.0", # Protocol 3
"4.0", # Protocol 4
] # Old format versions we can read
# This is the highest protocol number we know how to read.
HIGHEST_PROTOCOL = 4
# The protocol we write by default. May be less than HIGHEST_PROTOCOL.
# We intentionally write a protocol that Python 2.x cannot read;
# there are too many issues with that.
DEFAULT_PROTOCOL = 3
class PickleError(Exception):
"""A common base class for the other pickling exceptions."""
pass
class PicklingError(PickleError):
"""This exception is raised when an unpicklable object is passed to the
dump() method.
"""
pass
class UnpicklingError(PickleError):
"""This exception is raised when there is a problem unpickling an object,
such as a security violation.
Note that other exceptions may also be raised during unpickling, including
(but not necessarily limited to) AttributeError, EOFError, ImportError,
and IndexError.
"""
pass
# An instance of _Stop is raised by Unpickler.load_stop() in response to
# the STOP opcode, passing the object that is the result of unpickling.
class _Stop(Exception):
def __init__(self, value):
self.value = value
# Jython has PyStringMap; it's a dict subclass with string keys
try:
from org.python.core import PyStringMap
except ImportError:
PyStringMap = None
# Pickle opcodes. See pickletools.py for extensive docs. The listing
# here is in kind-of alphabetical order of 1-character pickle code.
# pickletools groups them by purpose.
MARK = b'(' # push special markobject on stack
STOP = b'.' # every pickle ends with STOP
POP = b'0' # discard topmost stack item
POP_MARK = b'1' # discard stack top through topmost markobject
DUP = b'2' # duplicate top stack item
FLOAT = b'F' # push float object; decimal string argument
INT = b'I' # push integer or bool; decimal string argument
BININT = b'J' # push four-byte signed int
BININT1 = b'K' # push 1-byte unsigned int
LONG = b'L' # push long; decimal string argument
BININT2 = b'M' # push 2-byte unsigned int
NONE = b'N' # push None
PERSID = b'P' # push persistent object; id is taken from string arg
BINPERSID = b'Q' # " " " ; " " " " stack
REDUCE = b'R' # apply callable to argtuple, both on stack
STRING = b'S' # push string; NL-terminated string argument
BINSTRING = b'T' # push string; counted binary string argument
SHORT_BINSTRING= b'U' # " " ; " " " " < 256 bytes
UNICODE = b'V' # push Unicode string; raw-unicode-escaped'd argument
BINUNICODE = b'X' # " " " ; counted UTF-8 string argument
APPEND = b'a' # append stack top to list below it
BUILD = b'b' # call __setstate__ or __dict__.update()
GLOBAL = b'c' # push self.find_class(modname, name); 2 string args
DICT = b'd' # build a dict from stack items
EMPTY_DICT = b'}' # push empty dict
APPENDS = b'e' # extend list on stack by topmost stack slice
GET = b'g' # push item from memo on stack; index is string arg
BINGET = b'h' # " " " " " " ; " " 1-byte arg
INST = b'i' # build & push class instance
LONG_BINGET = b'j' # push item from memo on stack; index is 4-byte arg
LIST = b'l' # build list from topmost stack items
EMPTY_LIST = b']' # push empty list
OBJ = b'o' # build & push class instance
PUT = b'p' # store stack top in memo; index is string arg
BINPUT = b'q' # " " " " " ; " " 1-byte arg
LONG_BINPUT = b'r' # " " " " " ; " " 4-byte arg
SETITEM = b's' # add key+value pair to dict
TUPLE = b't' # build tuple from topmost stack items
EMPTY_TUPLE = b')' # push empty tuple
SETITEMS = b'u' # modify dict by adding topmost key+value pairs
BINFLOAT = b'G' # push float; arg is 8-byte float encoding
TRUE = b'I01
' # not an opcode; see INT docs in pickletools.py
FALSE = b'I00
' # not an opcode; see INT docs in pickletools.py
# Protocol 2
PROTO = b'\x80' # identify pickle protocol
NEWOBJ = b'\x81' # build object by applying cls.__new__ to argtuple
EXT1 = b'\x82' # push object from extension registry; 1-byte index
EXT2 = b'\x83' # ditto, but 2-byte index
EXT4 = b'\x84' # ditto, but 4-byte index
TUPLE1 = b'\x85' # build 1-tuple from stack top
TUPLE2 = b'\x86' # build 2-tuple from two topmost stack items
TUPLE3 = b'\x87' # build 3-tuple from three topmost stack items
NEWTRUE = b'\x88' # push True
NEWFALSE = b'\x89' # push False
LONG1 = b'\x8a' # push long from < 256 bytes
LONG4 = b'\x8b' # push really big long
_tuplesize2code = [EMPTY_TUPLE, TUPLE1, TUPLE2, TUPLE3]
# Protocol 3 (Python 3.x)
BINBYTES = b'B' # push bytes; counted binary string argument
SHORT_BINBYTES = b'C' # " " ; " " " " < 256 bytes
# Protocol 4
SHORT_BINUNICODE = b'\x8c' # push short string; UTF-8 length < 256 bytes
BINUNICODE8 = b'\x8d' # push very long string
BINBYTES8 = b'\x8e' # push very long bytes string
EMPTY_SET = b'\x8f' # push empty set on the stack
ADDITEMS = b'\x90' # modify set by adding topmost stack items
FROZENSET = b'\x91' # build frozenset from topmost stack items
NEWOBJ_EX = b'\x92' # like NEWOBJ but work with keyword only arguments
STACK_GLOBAL = b'\x93' # same as GLOBAL but using names on the stacks
MEMOIZE = b'\x94' # store top of the stack in memo
FRAME = b'\x95' # indicate the beginning of a new frame
__all__.extend([x for x in dir() if re.match("[A-Z][A-Z0-9_]+$", x)])
class _Framer:
_FRAME_SIZE_TARGET = 64 * 1024
def __init__(self, file_write):
self.file_write = file_write
self.current_frame = None
def start_framing(self):
self.current_frame = io.BytesIO()
def end_framing(self):
if self.current_frame and self.current_frame.tell() > 0:
self.commit_frame(force=True)
self.current_frame = None
def commit_frame(self, force=False):
if self.current_frame:
f = self.current_frame
if f.tell() >= self._FRAME_SIZE_TARGET or force:
with f.getbuffer() as data:
n = len(data)
write = self.file_write
write(FRAME)
write(pack("", n))
write(data)
f.seek(0)
f.truncate()
def write(self, data):
if self.current_frame:
return self.current_frame.write(data)
else:
return self.file_write(data)
class _Unframer:
def __init__(self, file_read, file_readline, file_tell=None):
self.file_read = file_read
self.file_readline = file_readline
self.current_frame = None
def read(self, n):
if self.current_frame:
data = self.current_frame.read(n)
if not data and n != 0:
self.current_frame = None
return self.file_read(n)
if len(data) < n:
raise UnpicklingError(
"pickle exhausted before end of frame")
return data
else:
return self.file_read(n)
def readline(self):
if self.current_frame:
data = self.current_frame.readline()
if not data:
self.current_frame = None
return self.file_readline()
if data[-1] != b'
'[0]:
raise UnpicklingError(
"pickle exhausted before end of frame")
return data
else:
return self.file_readline()
def load_frame(self, frame_size):
if self.current_frame and self.current_frame.read() != b'':
raise UnpicklingError(
"beginning of a new frame before end of current frame")
self.current_frame = io.BytesIO(self.file_read(frame_size))
# Tools used for pickling.
def _getattribute(obj, name):
for subpath in name.split('.'):
if subpath == '
'
# Return a GET (BINGET, LONG_BINGET) opcode string, with argument i.
def get(self, i):
if self.bin:
if i < 256:
return BINGET + pack("", i)
else:
return LONG_BINGET + pack("", i)
return GET + repr(i).encode("ascii") + b'
'
def save(self, obj, save_persistent_id=True):
self.framer.commit_frame()
# Check for persistent id (defined by a subclass)
pid = self.persistent_id(obj)
if pid is not None and save_persistent_id:
self.save_pers(pid)
return
# Check the memo
x = self.memo.get(id(obj))
if x is not None:
self.write(self.get(x[0]))
return
# Check the type dispatch table
t = type(obj)
f = self.dispatch.get(t)
if f is not None:
f(self, obj) # Call unbound method with explicit self
return
# Check private dispatch table if any, or else copyreg.dispatch_table
reduce = getattr(self, 'dispatch_table', dispatch_table).get(t)
if reduce is not None:
rv = reduce(obj)
else:
# Check for a class with a custom metaclass; treat as regular class
try:
issc = issubclass(t, type)
except TypeError: # t is not a class (old Boost; see SF #502085)
issc = False
if issc:
self.save_global(obj)
return
# Check for a __reduce_ex__ method, fall back to __reduce__
reduce = getattr(obj, "__reduce_ex__", None)
if reduce is not None:
rv = reduce(self.proto)
else:
reduce = getattr(obj, "__reduce__", None)
if reduce is not None:
rv = reduce()
else:
raise PicklingError("Can't pickle %r object: %r" %
(t.__name__, obj))
# Check for string returned by reduce(), meaning "save as global"
if isinstance(rv, str):
self.save_global(obj, rv)
return
# Assert that reduce() returned a tuple
if not isinstance(rv, tuple):
raise PicklingError("%s must return string or tuple" % reduce)
# Assert that it returned an appropriately sized tuple
l = len(rv)
if not (2 <= l <= 5):
raise PicklingError("Tuple returned by %s must have "
"two to five elements" % reduce)
# Save the reduce() output and finally memoize the object
self.save_reduce(obj=obj, *rv)
def persistent_id(self, obj):
# This exists so a subclass can override it
return None
def save_pers(self, pid):
# Save a persistent id reference
if self.bin:
self.save(pid, save_persistent_id=False)
self.write(BINPERSID)
else:
self.write(PERSID + str(pid).encode("ascii") + b'
')
def save_reduce(self, func, args, state=None, listitems=None,
dictitems=None, obj=None):
# This API is called by some subclasses
if not isinstance(args, tuple):
raise PicklingError("args from save_reduce() must be a tuple")
if not callable(func):
raise PicklingError("func from save_reduce() must be callable")
save = self.save
write = self.write
func_name = getattr(func, "__name__", "")
if self.proto >= 4 and func_name == "__newobj_ex__":
cls, args, kwargs = args
if not hasattr(cls, "__new__"):
raise PicklingError("args[0] from {} args has no __new__"
.format(func_name))
if obj is not None and cls is not obj.__class__:
raise PicklingError("args[0] from {} args has the wrong class"
.format(func_name))
save(cls)
save(args)
save(kwargs)
write(NEWOBJ_EX)
elif self.proto >= 2 and func_name == "__newobj__":
# A __reduce__ implementation can direct protocol 2 or newer to
# use the more efficient NEWOBJ opcode, while still
# allowing protocol 0 and 1 to work normally. For this to
# work, the function returned by __reduce__ should be
# called __newobj__, and its first argument should be a
# class. The implementation for __newobj__
# should be as follows, although pickle has no way to
# verify this:
#
# def __newobj__(cls, *args):
# return cls.__new__(cls, *args)
#
# Protocols 0 and 1 will pickle a reference to __newobj__,
# while protocol 2 (and above) will pickle a reference to
# cls, the remaining args tuple, and the NEWOBJ code,
# which calls cls.__new__(cls, *args) at unpickling time
# (see load_newobj below). If __reduce__ returns a
# three-tuple, the state from the third tuple item will be
# pickled regardless of the protocol, calling __setstate__
# at unpickling time (see load_build below).
#
# Note that no standard __newobj__ implementation exists;
# you have to provide your own. This is to enforce
# compatibility with Python 2.2 (pickles written using
# protocol 0 or 1 in Python 2.3 should be unpicklable by
# Python 2.2).
cls = args[0]
if not hasattr(cls, "__new__"):
raise PicklingError(
"args[0] from __newobj__ args has no __new__")
if obj is not None and cls is not obj.__class__:
raise PicklingError(
"args[0] from __newobj__ args has the wrong class")
args = args[1:]
save(cls)
save(args)
write(NEWOBJ)
else:
save(func)
save(args)
write(REDUCE)
if obj is not None:
# If the object is already in the memo, this means it is
# recursive. In this case, throw away everything we put on the
# stack, and fetch the object back from the memo.
if id(obj) in self.memo:
write(POP + self.get(self.memo[id(obj)][0]))
else:
self.memoize(obj)
# More new special cases (that work with older protocols as
# well): when __reduce__ returns a tuple with 4 or 5 items,
# the 4th and 5th item should be iterators that provide list
# items and dict items (as (key, value) tuples), or None.
if listitems is not None:
self._batch_appends(listitems)
if dictitems is not None:
self._batch_setitems(dictitems)
if state is not None:
save(state)
write(BUILD)
# Methods below this point are dispatched through the dispatch table
dispatch = {}
def save_none(self, obj):
self.write(NONE)
dispatch[type(None)] = save_none
def save_bool(self, obj):
if self.proto >= 2:
self.write(NEWTRUE if obj else NEWFALSE)
else:
self.write(TRUE if obj else FALSE)
dispatch[bool] = save_bool
def save_long(self, obj):
if self.bin:
# If the int is small enough to fit in a signed 4-byte 2's-comp
# format, we can store it more efficiently than the general
# case.
# First one- and two-byte unsigned ints:
if obj >= 0:
if obj <= 0xff:
self.write(BININT1 + pack("", obj))
return
if obj <= 0xffff:
self.write(BININT2 + pack("", obj))
return
# Next check for 4-byte signed ints:
if -0x80000000 <= obj <= 0x7fffffff:
self.write(BININT + pack("", obj))
return
if self.proto >= 2:
encoded = encode_long(obj)
n = len(encoded)
if n < 256:
self.write(LONG1 + pack("", n) + encoded)
else:
self.write(LONG4 + pack("", n) + encoded)
return
self.write(LONG + repr(obj).encode("ascii") + b'L
')
dispatch[int] = save_long
def save_float(self, obj):
if self.bin:
self.write(BINFLOAT + pack('>d', obj))
else:
self.write(FLOAT + repr(obj).encode("ascii") + b'
')
dispatch[float] = save_float
def save_bytes(self, obj):
if self.proto < 3:
if not obj: # bytes object is empty
self.save_reduce(bytes, (), obj=obj)
else:
self.save_reduce(codecs.encode,
(str(obj, 'latin1'), 'latin1'), obj=obj)
return
n = len(obj)
if n <= 0xff:
self.write(SHORT_BINBYTES + pack("", n) + obj)
elif n > 0xffffffff and self.proto >= 4:
self.write(BINBYTES8 + pack("", n) + obj)
else:
self.write(BINBYTES + pack("", n) + obj)
self.memoize(obj)
dispatch[bytes] = save_bytes
def save_str(self, obj):
if self.bin:
encoded = obj.encode('utf-8', 'surrogatepass')
n = len(encoded)
if n <= 0xff and self.proto >= 4:
self.write(SHORT_BINUNICODE + pack("", n) + encoded)
elif n > 0xffffffff and self.proto >= 4:
self.write(BINUNICODE8 + pack("", n) + encoded)
else:
self.write(BINUNICODE + pack("", n) + encoded)
else:
obj = obj.replace("\\", "\\u005c")
obj = obj.replace("
", "\\u000a")
self.write(UNICODE + obj.encode('raw-unicode-escape') +
b'
')
self.memoize(obj)
dispatch[str] = save_str
def save_tuple(self, obj):
if not obj: # tuple is empty
if self.bin:
self.write(EMPTY_TUPLE)
else:
self.write(MARK + TUPLE)
return
n = len(obj)
save = self.save
memo = self.memo
if n <= 3 and self.proto >= 2:
for element in obj:
save(element)
# Subtle. Same as in the big comment below.
if id(obj) in memo:
get = self.get(memo[id(obj)][0])
self.write(POP * n + get)
else:
self.write(_tuplesize2code[n])
self.memoize(obj)
return
# proto 0 or proto 1 and tuple isn't empty, or proto > 1 and tuple
# has more than 3 elements.
write = self.write
write(MARK)
for element in obj:
save(element)
if id(obj) in memo:
# Subtle. d was not in memo when we entered save_tuple(), so
# the process of saving the tuple's elements must have saved
# the tuple itself: the tuple is recursive. The proper action
# now is to throw away everything we put on the stack, and
# simply GET the tuple (it's already constructed). This check
# could have been done in the "for element" loop instead, but
# recursive tuples are a rare thing.
get = self.get(memo[id(obj)][0])
if self.bin:
write(POP_MARK + get)
else: # proto 0 -- POP_MARK not available
write(POP * (n+1) + get)
return
# No recursion.
write(TUPLE)
self.memoize(obj)
dispatch[tuple] = save_tuple
def save_list(self, obj):
if self.bin:
self.write(EMPTY_LIST)
else: # proto 0 -- can't use EMPTY_LIST
self.write(MARK + LIST)
self.memoize(obj)
self._batch_appends(obj)
dispatch[list] = save_list
_BATCHSIZE = 1000
def _batch_appends(self, items):
# Helper to batch up APPENDS sequences
save = self.save
write = self.write
if not self.bin:
for x in items:
save(x)
write(APPEND)
return
it = iter(items)
while True:
tmp = list(islice(it, self._BATCHSIZE))
n = len(tmp)
if n > 1:
write(MARK)
for x in tmp:
save(x)
write(APPENDS)
elif n:
save(tmp[0])
write(APPEND)
# else tmp is empty, and we're done
if n < self._BATCHSIZE:
return
def save_dict(self, obj):
if self.bin:
self.write(EMPTY_DICT)
else: # proto 0 -- can't use EMPTY_DICT
self.write(MARK + DICT)
self.memoize(obj)
self._batch_setitems(obj.items())
dispatch[dict] = save_dict
if PyStringMap is not None:
dispatch[PyStringMap] = save_dict
def _batch_setitems(self, items):
# Helper to batch up SETITEMS sequences; proto >= 1 only
save = self.save
write = self.write
if not self.bin:
for k, v in items:
save(k)
save(v)
write(SETITEM)
return
it = iter(items)
while True:
tmp = list(islice(it, self._BATCHSIZE))
n = len(tmp)
if n > 1:
write(MARK)
for k, v in tmp:
save(k)
save(v)
write(SETITEMS)
elif n:
k, v = tmp[0]
save(k)
save(v)
write(SETITEM)
# else tmp is empty, and we're done
if n < self._BATCHSIZE:
return
def save_set(self, obj):
save = self.save
write = self.write
if self.proto < 4:
self.save_reduce(set, (list(obj),), obj=obj)
return
write(EMPTY_SET)
self.memoize(obj)
it = iter(obj)
while True:
batch = list(islice(it, self._BATCHSIZE))
n = len(batch)
if n > 0:
write(MARK)
for item in batch:
save(item)
write(ADDITEMS)
if n < self._BATCHSIZE:
return
dispatch[set] = save_set
def save_frozenset(self, obj):
save = self.save
write = self.write
if self.proto < 4:
self.save_reduce(frozenset, (list(obj),), obj=obj)
return
write(MARK)
for item in obj:
save(item)
if id(obj) in self.memo:
# If the object is already in the memo, this means it is
# recursive. In this case, throw away everything we put on the
# stack, and fetch the object back from the memo.
write(POP_MARK + self.get(self.memo[id(obj)][0]))
return
write(FROZENSET)
self.memoize(obj)
dispatch[frozenset] = save_frozenset
def save_global(self, obj, name=None):
write = self.write
memo = self.memo
if name is None:
name = getattr(obj, '__qualname__', None)
if name is None:
name = obj.__name__
module_name = whichmodule(obj, name)
try:
__import__(module_name, level=0)
module = sys.modules[module_name]
obj2, parent = _getattribute(module, name)
except (ImportError, KeyError, AttributeError):
raise PicklingError(
"Can't pickle %r: it's not found as %s.%s" %
(obj, module_name, name))
else:
if obj2 is not obj:
raise PicklingError(
"Can't pickle %r: it's not the same object as %s.%s" %
(obj, module_name, name))
if self.proto >= 2:
code = _extension_registry.get((module_name, name))
if code:
assert code > 0
if code <= 0xff:
write(EXT1 + pack("", code))
elif code <= 0xffff:
write(EXT2 + pack("", code))
else:
write(EXT4 + pack("", code))
return
lastname = name.rpartition('.')[2]
if parent is module:
name = lastname
# Non-ASCII identifiers are supported only with protocols >= 3.
if self.proto >= 4:
self.save(module_name)
self.save(name)
write(STACK_GLOBAL)
elif parent is not module:
self.save_reduce(getattr, (parent, lastname))
elif self.proto >= 3:
write(GLOBAL + bytes(module_name, "utf-8") + b'
' +
bytes(name, "utf-8") + b'
')
else:
if self.fix_imports:
r_name_mapping = _compat_pickle.REVERSE_NAME_MAPPING
r_import_mapping = _compat_pickle.REVERSE_IMPORT_MAPPING
if (module_name, name) in r_name_mapping:
module_name, name = r_name_mapping[(module_name, name)]
elif module_name in r_import_mapping:
module_name = r_import_mapping[module_name]
try:
write(GLOBAL + bytes(module_name, "ascii") + b'
' +
bytes(name, "ascii") + b'
')
except UnicodeEncodeError:
raise PicklingError(
"can't pickle global identifier '%s.%s' using "
"pickle protocol %i" % (module, name, self.proto))
self.memoize(obj)
def save_type(self, obj):
if obj is type(None):
return self.save_reduce(type, (None,), obj=obj)
elif obj is type(NotImplemented):
return self.save_reduce(type, (NotImplemented,), obj=obj)
elif obj is type(...):
return self.save_reduce(type, (...,), obj=obj)
return self.save_global(obj)
dispatch[FunctionType] = save_global
dispatch[type] = save_type
# Unpickling machinery
class _Unpickler:
def __init__(self, file, *, fix_imports=True,
encoding="ASCII", errors="strict"):
"""This takes a binary file for reading a pickle data stream.
The protocol version of the pickle is detected automatically, so
no proto argument is needed.
The argument *file* must have two methods, a read() method that
takes an integer argument, and a readline() method that requires
no arguments. Both methods should return bytes. Thus *file*
can be a binary file object opened for reading, an io.BytesIO
object, or any other custom object that meets this interface.
The file-like object must have two methods, a read() method
that takes an integer argument, and a readline() method that
requires no arguments. Both methods should return bytes.
Thus file-like object can be a binary file object opened for
reading, a BytesIO object, or any other custom object that
meets this interface.
Optional keyword arguments are *fix_imports*, *encoding* and
*errors*, which are used to control compatibility support for
pickle stream generated by Python 2. If *fix_imports* is True,
pickle will try to map the old Python 2 names to the new names
used in Python 3. The *encoding* and *errors* tell pickle how
to decode 8-bit string instances pickled by Python 2; these
default to 'ASCII' and 'strict', respectively. *encoding* can be
'bytes' to read theses 8-bit string instances as bytes objects.
"""
self._file_readline = file.readline
self._file_read = file.read
self.memo = {}
self.encoding = encoding
self.errors = errors
self.proto = 0
self.fix_imports = fix_imports
def load(self):
"""Read a pickled object representation from the open file.
Return the reconstituted object hierarchy specified in the file.
"""
# Check whether Unpickler was initialized correctly. This is
# only needed to mimic the behavior of _pickle.Unpickler.dump().
if not hasattr(self, "_file_read"):
raise UnpicklingError("Unpickler.__init__() was not called by "
"%s.__init__()" % (self.__class__.__name__,))
self._unframer = _Unframer(self._file_read, self._file_readline)
self.read = self._unframer.read
self.readline = self._unframer.readline
self.mark = object() # any new unique object
self.stack = []
self.append = self.stack.append
self.proto = 0
read = self.read
dispatch = self.dispatch
try:
while True:
key = read(1)
if not key:
raise EOFError
assert isinstance(key, bytes_types)
dispatch[key[0]](self)
except _Stop as stopinst:
return stopinst.value
# Return largest index k such that self.stack[k] is self.mark.
# If the stack doesn't contain a mark, eventually raises IndexError.
# This could be sped by maintaining another stack, of indices at which
# the mark appears. For that matter, the latter stack would suffice,
# and we wouldn't need to push mark objects on self.stack at all.
# Doing so is probably a good thing, though, since if the pickle is
# corrupt (or hostile) we may get a clue from finding self.mark embedded
# in unpickled objects.
def marker(self):
stack = self.stack
mark = self.mark
k = len(stack)-1
while stack[k] is not mark: k = k-1
return k
def persistent_load(self, pid):
raise UnpicklingError("unsupported persistent id encountered")
dispatch = {}
def load_proto(self):
proto = self.read(1)[0]
if not 0 <= proto <= HIGHEST_PROTOCOL:
raise ValueError("unsupported pickle protocol: %d" % proto)
self.proto = proto
dispatch[PROTO[0]] = load_proto
def load_frame(self):
frame_size, = unpack('', self.read(8))
if frame_size > sys.maxsize:
raise ValueError("frame size > sys.maxsize: %d" % frame_size)
self._unframer.load_frame(frame_size)
dispatch[FRAME[0]] = load_frame
def load_persid(self):
pid = self.readline()[:-1].decode("ascii")
self.append(self.persistent_load(pid))
dispatch[PERSID[0]] = load_persid
def load_binpersid(self):
pid = self.stack.pop()
self.append(self.persistent_load(pid))
dispatch[BINPERSID[0]] = load_binpersid
def load_none(self):
self.append(None)
dispatch[NONE[0]] = load_none
def load_false(self):
self.append(False)
dispatch[NEWFALSE[0]] = load_false
def load_true(self):
self.append(True)
dispatch[NEWTRUE[0]] = load_true
def load_int(self):
data = self.readline()
if data == FALSE[1:]:
val = False
elif data == TRUE[1:]:
val = True
else:
val = int(data, 0)
self.append(val)
dispatch[INT[0]] = load_int
def load_binint(self):
self.append(unpack('', self.read(4))[0])
dispatch[BININT[0]] = load_binint
def load_binint1(self):
self.append(self.read(1)[0])
dispatch[BININT1[0]] = load_binint1
def load_binint2(self):
self.append(unpack('', self.read(2))[0])
dispatch[BININT2[0]] = load_binint2
def load_long(self):
val = self.readline()[:-1]
if val and val[-1] == b'L'[0]:
val = val[:-1]
self.append(int(val, 0))
dispatch[LONG[0]] = load_long
def load_long1(self):
n = self.read(1)[0]
data = self.read(n)
self.append(decode_long(data))
dispatch[LONG1[0]] = load_long1
def load_long4(self):
n, = unpack('', self.read(4))
if n < 0:
# Corrupt or hostile pickle -- we never write one like this
raise UnpicklingError("LONG pickle has negative byte count")
data = self.read(n)
self.append(decode_long(data))
dispatch[LONG4[0]] = load_long4
def load_float(self):
self.append(float(self.readline()[:-1]))
dispatch[FLOAT[0]] = load_float
def load_binfloat(self):
self.append(unpack('>d', self.read(8))[0])
dispatch[BINFLOAT[0]] = load_binfloat
def _decode_string(self, value):
# Used to allow strings from Python 2 to be decoded either as
# bytes or Unicode strings. This should be used only with the
# STRING, BINSTRING and SHORT_BINSTRING opcodes.
if self.encoding == "bytes":
return value
else:
return value.decode(self.encoding, self.errors)
def load_string(self):
data = self.readline()[:-1]
# Strip outermost quotes
if len(data) >= 2 and data[0] == data[-1] and data[0] in b'"\'':
data = data[1:-1]
else:
raise UnpicklingError("the STRING opcode argument must be quoted")
self.append(self._decode_string(codecs.escape_decode(data)[0]))
dispatch[STRING[0]] = load_string
def load_binstring(self):
# Deprecated BINSTRING uses signed 32-bit length
len, = unpack('', self.read(4))
if len < 0:
raise UnpicklingError("BINSTRING pickle has negative byte count")
data = self.read(len)
self.append(self._decode_string(data))
dispatch[BINSTRING[0]] = load_binstring
def load_binbytes(self):
len, = unpack('', self.read(4))
if len > maxsize:
raise UnpicklingError("BINBYTES exceeds system's maximum size "
"of %d bytes" % maxsize)
self.append(self.read(len))
dispatch[BINBYTES[0]] = load_binbytes
def load_unicode(self):
self.append(str(self.readline()[:-1], 'raw-unicode-escape'))
dispatch[UNICODE[0]] = load_unicode
def load_binunicode(self):
len, = unpack('', self.read(4))
if len > maxsize:
raise UnpicklingError("BINUNICODE exceeds system's maximum size "
"of %d bytes" % maxsize)
self.append(str(self.read(len), 'utf-8', 'surrogatepass'))
dispatch[BINUNICODE[0]] = load_binunicode
def load_binunicode8(self):
len, = unpack('', self.read(8))
if len > maxsize:
raise UnpicklingError("BINUNICODE8 exceeds system's maximum size "
"of %d bytes" % maxsize)
self.append(str(self.read(len), 'utf-8', 'surrogatepass'))
dispatch[BINUNICODE8[0]] = load_binunicode8
def load_binbytes8(self):
len, = unpack('', self.read(8))
if len > maxsize:
raise UnpicklingError("BINBYTES8 exceeds system's maximum size "
"of %d bytes" % maxsize)
self.append(self.read(len))
dispatch[BINBYTES8[0]] = load_binbytes8
def load_short_binstring(self):
len = self.read(1)[0]
data = self.read(len)
self.append(self._decode_string(data))
dispatch[SHORT_BINSTRING[0]] = load_short_binstring
def load_short_binbytes(self):
len = self.read(1)[0]
self.append(self.read(len))
dispatch[SHORT_BINBYTES[0]] = load_short_binbytes
def load_short_binunicode(self):
len = self.read(1)[0]
self.append(str(self.read(len), 'utf-8', 'surrogatepass'))
dispatch[SHORT_BINUNICODE[0]] = load_short_binunicode
def load_tuple(self):
k = self.marker()
self.stack[k:] = [tuple(self.stack[k+1:])]
dispatch[TUPLE[0]] = load_tuple
def load_empty_tuple(self):
self.append(())
dispatch[EMPTY_TUPLE[0]] = load_empty_tuple
def load_tuple1(self):
self.stack[-1] = (self.stack[-1],)
dispatch[TUPLE1[0]] = load_tuple1
def load_tuple2(self):
self.stack[-2:] = [(self.stack[-2], self.stack[-1])]
dispatch[TUPLE2[0]] = load_tuple2
def load_tuple3(self):
self.stack[-3:] = [(self.stack[-3], self.stack[-2], self.stack[-1])]
dispatch[TUPLE3[0]] = load_tuple3
def load_empty_list(self):
self.append([])
dispatch[EMPTY_LIST[0]] = load_empty_list
def load_empty_dictionary(self):
self.append({})
dispatch[EMPTY_DICT[0]] = load_empty_dictionary
def load_empty_set(self):
self.append(set())
dispatch[EMPTY_SET[0]] = load_empty_set
def load_frozenset(self):
k = self.marker()
self.stack[k:] = [frozenset(self.stack[k+1:])]
dispatch[FROZENSET[0]] = load_frozenset
def load_list(self):
k = self.marker()
self.stack[k:] = [self.stack[k+1:]]
dispatch[LIST[0]] = load_list
def load_dict(self):
k = self.marker()
items = self.stack[k+1:]
d = {items[i]: items[i+1]
for i in range(0, len(items), 2)}
self.stack[k:] = [d]
dispatch[DICT[0]] = load_dict
# INST and OBJ differ only in how they get a class object. It's not
# only sensible to do the rest in a common routine, the two routines
# previously diverged and grew different bugs.
# klass is the class to instantiate, and k points to the topmost mark
# object, following which are the arguments for klass.__init__.
def _instantiate(self, klass, k):
args = tuple(self.stack[k+1:])
del self.stack[k:]
if (args or not isinstance(klass, type) or
hasattr(klass, "__getinitargs__")):
try:
value = klass(*args)
except TypeError as err:
raise TypeError("in constructor for %s: %s" %
(klass.__name__, str(err)), sys.exc_info()[2])
else:
value = klass.__new__(klass)
self.append(value)
def load_inst(self):
module = self.readline()[:-1].decode("ascii")
name = self.readline()[:-1].decode("ascii")
klass = self.find_class(module, name)
self._instantiate(klass, self.marker())
dispatch[INST[0]] = load_inst
def load_obj(self):
# Stack is ... markobject classobject arg1 arg2 ...
k = self.marker()
klass = self.stack.pop(k+1)
self._instantiate(klass, k)
dispatch[OBJ[0]] = load_obj
def load_newobj(self):
args = self.stack.pop()
cls = self.stack.pop()
obj = cls.__new__(cls, *args)
self.append(obj)
dispatch[NEWOBJ[0]] = load_newobj
def load_newobj_ex(self):
kwargs = self.stack.pop()
args = self.stack.pop()
cls = self.stack.pop()
obj = cls.__new__(cls, *args, **kwargs)
self.append(obj)
dispatch[NEWOBJ_EX[0]] = load_newobj_ex
def load_global(self):
module = self.readline()[:-1].decode("utf-8")
name = self.readline()[:-1].decode("utf-8")
klass = self.find_class(module, name)
self.append(klass)
dispatch[GLOBAL[0]] = load_global
def load_stack_global(self):
name = self.stack.pop()
module = self.stack.pop()
if type(name) is not str or type(module) is not str:
raise UnpicklingError("STACK_GLOBAL requires str")
self.append(self.find_class(module, name))
dispatch[STACK_GLOBAL[0]] = load_stack_global
def load_ext1(self):
code = self.read(1)[0]
self.get_extension(code)
dispatch[EXT1[0]] = load_ext1
def load_ext2(self):
code, = unpack('', self.read(2))
self.get_extension(code)
dispatch[EXT2[0]] = load_ext2
def load_ext4(self):
code, = unpack('', self.read(4))
self.get_extension(code)
dispatch[EXT4[0]] = load_ext4
def get_extension(self, code):
nil = []
obj = _extension_cache.get(code, nil)
if obj is not nil:
self.append(obj)
return
key = _inverted_registry.get(code)
if not key:
if code <= 0: # note that 0 is forbidden
# Corrupt or hostile pickle.
raise UnpicklingError("EXT specifies code <= 0")
raise ValueError("unregistered extension code %d" % code)
obj = self.find_class(*key)
_extension_cache[code] = obj
self.append(obj)
def find_class(self, module, name):
# Subclasses may override this.
if self.proto < 3 and self.fix_imports:
if (module, name) in _compat_pickle.NAME_MAPPING:
module, name = _compat_pickle.NAME_MAPPING[(module, name)]
elif module in _compat_pickle.IMPORT_MAPPING:
module = _compat_pickle.IMPORT_MAPPING[module]
__import__(module, level=0)
if self.proto >= 4:
return _getattribute(sys.modules[module], name)[0]
else:
return getattr(sys.modules[module], name)
def load_reduce(self):
stack = self.stack
args = stack.pop()
func = stack[-1]
stack[-1] = func(*args)
dispatch[REDUCE[0]] = load_reduce
def load_pop(self):
del self.stack[-1]
dispatch[POP[0]] = load_pop
def load_pop_mark(self):
k = self.marker()
del self.stack[k:]
dispatch[POP_MARK[0]] = load_pop_mark
def load_dup(self):
self.append(self.stack[-1])
dispatch[DUP[0]] = load_dup
def load_get(self):
i = int(self.readline()[:-1])
self.append(self.memo[i])
dispatch[GET[0]] = load_get
def load_binget(self):
i = self.read(1)[0]
self.append(self.memo[i])
dispatch[BINGET[0]] = load_binget
def load_long_binget(self):
i, = unpack('', self.read(4))
self.append(self.memo[i])
dispatch[LONG_BINGET[0]] = load_long_binget
def load_put(self):
i = int(self.readline()[:-1])
if i < 0:
raise ValueError("negative PUT argument")
self.memo[i] = self.stack[-1]
dispatch[PUT[0]] = load_put
def load_binput(self):
i = self.read(1)[0]
if i < 0:
raise ValueError("negative BINPUT argument")
self.memo[i] = self.stack[-1]
dispatch[BINPUT[0]] = load_binput
def load_long_binput(self):
i, = unpack('', self.read(4))
if i > maxsize:
raise ValueError("negative LONG_BINPUT argument")
self.memo[i] = self.stack[-1]
dispatch[LONG_BINPUT[0]] = load_long_binput
def load_memoize(self):
memo = self.memo
memo[len(memo)] = self.stack[-1]
dispatch[MEMOIZE[0]] = load_memoize
def load_append(self):
stack = self.stack
value = stack.pop()
list = stack[-1]
list.append(value)
dispatch[APPEND[0]] = load_append
def load_appends(self):
stack = self.stack
mark = self.marker()
list_obj = stack[mark - 1]
items = stack[mark + 1:]
if isinstance(list_obj, list):
list_obj.extend(items)
else:
append = list_obj.append
for item in items:
append(item)
del stack[mark:]
dispatch[APPENDS[0]] = load_appends
def load_setitem(self):
stack = self.stack
value = stack.pop()
key = stack.pop()
dict = stack[-1]
dict[key] = value
dispatch[SETITEM[0]] = load_setitem
def load_setitems(self):
stack = self.stack
mark = self.marker()
dict = stack[mark - 1]
for i in range(mark + 1, len(stack), 2):
dict[stack[i]] = stack[i + 1]
del stack[mark:]
dispatch[SETITEMS[0]] = load_setitems
def load_additems(self):
stack = self.stack
mark = self.marker()
set_obj = stack[mark - 1]
items = stack[mark + 1:]
if isinstance(set_obj, set):
set_obj.update(items)
else:
add = set_obj.add
for item in items:
add(item)
del stack[mark:]
dispatch[ADDITEMS[0]] = load_additems
def load_build(self):
stack = self.stack
state = stack.pop()
inst = stack[-1]
setstate = getattr(inst, "__setstate__", None)
if setstate is not None:
setstate(state)
return
slotstate = None
if isinstance(state, tuple) and len(state) == 2:
state, slotstate = state
if state:
inst_dict = inst.__dict__
intern = sys.intern
for k, v in state.items():
if type(k) is str:
inst_dict[intern(k)] = v
else:
inst_dict[k] = v
if slotstate:
for k, v in slotstate.items():
setattr(inst, k, v)
dispatch[BUILD[0]] = load_build
def load_mark(self):
self.append(self.mark)
dispatch[MARK[0]] = load_mark
def load_stop(self):
value = self.stack.pop()
raise _Stop(value)
dispatch[STOP[0]] = load_stop
# Shorthands
def _dump(obj, file, protocol=None, *, fix_imports=True):
_Pickler(file, protocol, fix_imports=fix_imports).dump(obj)
def _dumps(obj, protocol=None, *, fix_imports=True):
f = io.BytesIO()
_Pickler(f, protocol, fix_imports=fix_imports).dump(obj)
res = f.getvalue()
assert isinstance(res, bytes_types)
return res
def _load(file, *, fix_imports=True, encoding="ASCII", errors="strict"):
return _Unpickler(file, fix_imports=fix_imports,
encoding=encoding, errors=errors).load()
def _loads(s, *, fix_imports=True, encoding="ASCII", errors="strict"):
if isinstance(s, str):
raise TypeError("Can't load pickle from unicode string")
file = io.BytesIO(s)
return _Unpickler(file, fix_imports=fix_imports,
encoding=encoding, errors=errors).load()
# Use the faster _pickle if possible
try:
from _pickle import (
PickleError,
PicklingError,
UnpicklingError,
Pickler,
Unpickler,
dump,
dumps,
load,
loads
)
except ImportError:
Pickler, Unpickler = _Pickler, _Unpickler
dump, dumps, load, loads = _dump, _dumps, _load, _loads
# Doctest
def _test():
import doctest
return doctest.testmod()
if __name__ == "__main__":
import argparse
parser = argparse.ArgumentParser(
description='display contents of the pickle files')
parser.add_argument(
'pickle_file', type=argparse.FileType('br'),
nargs='*', help='the pickle file')
parser.add_argument(
'-t', '--test', action='store_true',
help='run self-test suite')
parser.add_argument(
'-v', action='store_true',
help='run verbosely; only affects self-test run')
args = parser.parse_args()
if args.test:
_test()
else:
if not args.pickle_file:
parser.print_help()
else:
import pprint
for f in args.pickle_file:
obj = load(f)
pprint.pprint(obj)
転載先:https://www.cnblogs.com/gengcx/p/7331120.html