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Following is the list of keywords displayed by running the above commands:

            ['False', 'None', 'True', 'and', 'as', 'assert', 'async', 'await', 'break',
            'class', 'continue', 'def', 'del', 'elif', 'else', 'except', 'finally', 'for',
            'from', 'global', 'if', 'import', 'in', 'is', 'lambda', 'nonlocal', 'not', 'or',
            'pass', 'raise', 'return', 'try', 'while', 'with', 'yield']

            Identifiers (Names)
            Identifiers are the user-defined names of variables, list, dictionary, tuples, classes etc. They identify an element
            in Python.
            Naming the identifiers follows rules as given below:
               • An identifier can have letters in uppercase or lowercase, numbers or underscore(_).
               • It cannot begin with a number.
               • No special characters like $, period(.), space, etc. are allowed.
               • It should not be a Python keyword.
               • Uppercase and lowercase letters are different.

            Example of invalid identifiers are:
            First name   :   Spaces not allowed.

            Last&Name  :    Cannot have special character.
            9thclass     :   Cannot begin with number

            else         :   Keyword not allowed.
            Example of valid identifiers are:

               Myclass, class9, Address, address, first_name, city, student_id, data123

            Variables

            Variable is a name given to a memory location to hold a specific value. It is just like a container that can hold any
            type of data that can be changed later in the program.

            Variable has:
               • A name that follows the rules of identifier naming conventions and is case sensitive.
               • A value that can be integer, float, string, boolean, etc.
            Unlike other programming languages, variables in Python are not created before. They are created automatically
            when a value is assigned to it using an = operator. A variable assigned with a value of one type can be re-
            assigned a new value of a different type as shown below:
              >>>a = 20
              >>>a
              20
              >>>a = "hello"
              >>>a
              'hello'
            There are different ways of assigning values to different variables in Python:
               • Method1: Assigning different values to different variable on different lines.

              >>>a = 5


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