Python - Datatypes : Dictionaries

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In this post, we are going to look at the dictionary in python, where it provide you the basic ability to access in O(1) time. Below we are going to show you how to
  • create dictionary
  • delete elemetn from a dictionary 
  • index an element through the key 

  • below is the code. 
    '''
    Created on 2012-10-23
    
    @author: Administrator
    file: DictionaryOps.py
    description: this file will demonstrate the use of Dictionaries in Python
    '''
    def dictionary_ops():
        x = {1: "one", 2: "two"}
        x['first']  = "one"
        x[("Delorme", "Ryan", 1995)] = (1, 2, 3)  # tuple can be the dictionary key and tuple can be the dictionary value , Keys must be of immutable types
        print("*** the dictionary")
        print(x)
        print("*** value to key 1")
        print(x[1])
        print("*** dictionary.get accepts default value")
        print(x.get(1, "not available"))
        del x[1]
        print ("*** after delete 1, the dictionary ")
        print(x)
    
    if __name__ == '__main__':
        dictionary_ops()