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    Characteristics of Keyword:
                     1.    We can’t use a Keyword as variable name.

                     2.   Keywords are used to define syntax and structure of Python language.

                     3.   Python keywords are case sensitive.

                     4.   Python 3.8 supports 35 such keywords.
                     Python Keywords: A few keywords are listed below:

                     False      break       for          import

                     True       None        is           and
                     def        from        if           or

                     Keyword Usage:

                     Suppose we want to assign False to a variable X:
                     X = False

                     Here, False is a keyword used to assign a Boolean false value.

                     2.4.2 Variable

                     Variable is just like a small container that can hold a value. A variable is simply a memory
                     location that is reserved to store some value.

                     In Python, a variable is created the moment you first assign a value to it.
                     For example:

                     X = 8

                     Here, X is a variable of integer type. In Python, the value assigned to a variable determines
                     its type.
                     X = “Computer”

                     Now, X is a string variable.

                     Therefore, a variable can change its type after it has been set. X was of integer type in
                     the first case, while it changed to string type later.
                     Why do we require variables?

                     You must have used variables in mathematical expressions. What do they do? If you have
                     written x = 5 * y, where y = 3, then what will be the value of x? You can see that the value

                     of x is dependent on the value of y. In this case, x and y are variables.
                     Now, if the value of y is changed by the user, the value of x automatically changes according
                     to the new value of y.

                     In computer programming, you need variables to hold user inputs, intermediate results, and
                     output.

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