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Python String | isidentifier ()


This built-in Python function is used to check if a string is a valid identifier or not. The method returns True if the string is a valid identifier, otherwise it returns False. 
Syntax :



The method does not take any parameters

Returned value:

The method can return one of the two values:

  • True: When the string is a valid identifier.
  • False: When the string is not a valid identifier.
  • The programs below show how the method works.

    # Python code to illustrate how it works isidentifier ()

    # String with spaces

    string = "Geeks for Geeks"

    print (string.isidentifier ())

    # Ideal identifier

    string = "GeeksforGeeks"

    print (string.isidentifier ())

    # Empty string

    string = ""

    print (string.isidentifier ())

    # Alphanumeric string

    string = "Geeks0for0Geeks"

    print (string.isidentifier ())

    # Starting with an integer

    string = " 54Geeks0for0Geeks "

    print (string.isidentifier ())


     False True False True False 

    Python String | isidentifier () Python functions: Questions

    Python String | isidentifier () String Variables: Questions


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