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Python Variables

Python is a dynamically typed language, which means that the type of a variable is determined at runtime. Variables are used to store data in a program. In Python, variables are created when they are first assigned a value. The value of a variable can be changed at any time during the execution of a program.

Variables in Python are case sensitive, which means that "myVariable" and "myvariable" are two different variables. Python variables can contain letters, numbers, and underscores, but they cannot start with a number.

Python has several built-in data types, including integers, floating-point numbers, strings, and booleans. Variables in Python can hold any of these data types.

Declaring Variables in Python

Variables in Python are declared using the assignment operator (=). The syntax for declaring a variable is:

variable_name = value

For example, to declare a variable called "x" and assign it the value 5, you would write:

x = 5

You can also declare multiple variables on the same line:

x, y, z = 1, 2, 3

This assigns the values 1, 2, and 3 to the variables x, y, and z, respectively.

Using Variables in Python

Once a variable has been declared, you can use it in your program. For example, to print the value of a variable to the console, you would write:

print(x)

This would print the value of the variable x to the console.

You can also perform operations on variables. For example, to add two variables together and store the result in a third variable, you would write:

x = 5
y = 10
z = x + y
print(z)

This would print the value 15 to the console.

Variable Naming Conventions

When naming variables in Python, it is important to follow certain conventions. Variable names should be descriptive and should not be too long. They should also follow the following rules:

  • Variable names should start with a lowercase letter.
  • Variable names should not contain spaces.
  • Variable names should not start with a number.
  • Variable names should be written in lowercase, with words separated by underscores.

For example, a variable name like "my_variable_name" is a good choice, while a variable name like "myVariableNameIsReallyLong" is not.

Conclusion

Python variables are used to store data in a program. They are created when they are first assigned a value and can hold any of Python's built-in data types. Variables in Python are case sensitive and should follow certain naming conventions.

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