Scope

What You’ll Learn

A variable is only available from inside the region it is created. This is called scope.

Local Scope

A variable created inside a function belongs to the local scope of that function, and can only be used inside that function.

def myfunc():
    x = 300
    print(x) # This works

myfunc()
# print(x) # THIS WILL CAUSE AN ERROR! x is not defined outside.

Global Scope

A variable created in the main body of the Python code is a global variable and belongs to the global scope. Global variables are available from within any scope, global and local.

x = 300 # Global variable

def myfunc():
    print(x) # Can access x from inside the function

myfunc()
print(x)

Shadowing

If you operate with the same variable name inside and outside of a function, Python will treat them as two separate variables.

x = 300

def myfunc():
    x = 200 # Local x shadows the global x
    print(x) # Prints 200

myfunc()
print(x) # Prints 300