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Some of the examples of valid identifiers are:  Num1, First_Name, Value, Scores_FirstTerm.

                 Some of the examples of invalid identifiers are: 1stsubject, My name, #mobile, City&Code, and True.
                 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 the assignment operator (=) Value to be assigned is always on the right side
                 of the equal to. A variable assigned with a value of one type can be re-assigned a new value of a different type as
                 shown below:

                 [1]:   a=9
                        print(a)
                        a="Orange"
                        print(a)

                        9
                        Orange

                 There are different ways of assigning values to different variables in Python:
                    • Method 1: Assigning different values to different variable in different lines.

                 [1]:   rollno = 5
                        strength = 10.5
                        name = "Amita"

                    • Method 2: Assigning different values to different variable in the same line.

                 [1]:   rollno, strength, name = 5, 10.5, "Amita"

                    • Method 3: Assigning same values to different variables in the same line.

                 [1]:   marks1 = marks2 = marks3 = 45


                 Data Types


                 Data types specify the kind of a value a variable can store. It helps us to identify the kind of operation that can
                 be performed on that specific data type. Every value in Python has a data type.

                                                                Data Types




                                   Numbers          None          Boolean      Sequences      Sets     Maps






                             int      float     complex              string     list      tuple      Dictionary


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