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Learn Python From Scratch to Expert.
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Creating Variables
Variables are containers for storing data values.
Unlike other programming languages, Python has no command for declaring a variable.
A variable is created the moment you first assign a value to it.
x = 5
y = "John"
print(x)
print(y)

Variables do not need to be declared with any particular type and can even change type after they have been set.

x = 4 # x is of type int
x = "Sally" # x is now of type str
print(x)

String variables can be declared either by using single or double quotes:

x = "John"
# is the same as
x = 'John'

Variable Names
A variable can have a short name (like x and y) or a more descriptive name (age, carname, total_volume). Rules for Python variables:
A variable name must start with a letter or the underscore character
A variable name cannot start with a number
A variable name can only contain alpha-numeric characters and underscores (A-z, 0-9, and _ )
Variable names are case-sensitive (age, Age and AGE are three different variables)

#Legal variable names:
myvar = "John"
my_var = "John"
_my_var = "John"
myVar = "John"
MYVAR = "John"
myvar2 = "John"

#Illegal variable names:
2myvar = "John"
my-var = "John"
my var = "John"

***Remember that variable names are case-sensitive

Assign Value to Multiple Variables
Python allows you to assign values to multiple variables in one line:
x, y, z = "Orange", "Banana", "Cherry"
print(x)
print(y)
print(z)

And you can assign the same value to multiple variables in one line:
x = y = z = "Orange"
print(x)
print(y)
print(z)

Output Variables
The Python print statement is often used to output variables.
To combine both text and a variable, Python uses the + character:

x = "awesome"
print("Python is " + x)

You can also use the + character to add a variable to another variable:
x = "Python is "
y = "awesome"
z = x + y
print(z)

For numbers, the + character works as a mathematical operator:
x = 5
y = 10
print(x + y)

If you try to combine a string and a number, Python will give you an error:
x = 5
y = "John"
print(x + y)

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