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    KEYWORDS AND IDENTIFIERS

                      In Python, keywords and identifiers are two important concepts that define the structure and
                      naming conventions of a program.

                      KEYWORDS

                      Keywords are  reserved words with special
                      meanings in Python, used for tasks like control      Python has 35 reserved keywords that cannot
                      flow (if, for, while), functions (def) and classes   be used as variable names.
                      (class). They cannot  be used  as variable
                      names. Here is a list of Python keywords:

                       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
                      You cannot use keywords as variable names. For example, you cannot name a variable ‘if’ or ‘for’.

                      IDENTIFIERS

                      An identifier is a name used to uniquely identify a variable, function, class or object in Python. It
                      represents the values you store, like numbers or text.

                      Examples of Identifiers:

                          Variable identifiers: age, score, temperature

                          Function identifiers: print_message(), calculate_sum()
                          Class identifiers: Person, Student

                             VARIABLES IN PYTHON

                      In  Python,  variables store values that  can be  accessed  or changed  later. Their names  are
                      identifiers and you don’t need to specify their type because Python is dynamically typed.

                      RULES FOR NAMING VARIABLES

                      When creating variable names, make sure to follow these rules:
                          Variable names can contain letters (a-z, A-Z), digits (0-9) and underscores (_).

                          Variable names must begin with a letter or an underscore (_), but not a number.
                          Variable names are case-sensitive, so ‘age’ and ‘Age’ are considered two different variables.

                          Variable names cannot use Python keywords (such as if, else, for) as variable names.
                          Variable names cannot contain spaces.

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