Understanding Python Scope

Not all variables can be accessed from anywhere in a program. The part of a program where a variable is accessible is called its scope. Scope defines the region in a program where a variable can be accessed. 

In Python, there are two main types of scope: 

1. Local Scope
2. Global Scope

Local Scope:

When we declare variables inside a function, these variables will have a local scope (within the function). We cannot access them outside the function. These types of variables are called local variables.

Examples:

• def func1():

  x = 300

  print(x)

func1()

Output: 300

As explained in the example above, the variable x is not available outside the function, but it is available for any function inside the function.

• def func2():

   x = 550

  def innerfunc():

    print(x)

innerfunc()

func2()

Output: 550

The local variable can be accessed from a function within the function.

• def func3():

s = “I love Pakistan”

print(s)

func3()

Output: I love Pakistan

Note: If we will try to use this local variable outside the function then let’s see what will happen.

Def func4()

a = “Python Programming”

print(“Pakistan”)

func4()

print(a)

Output: NameError: name ‘a’ is not defined

Global Scope:

Global variables are the ones that are defined and declared outside any function and are not specified in any function. They can be used by any part of the program

This means that a global variable can be accessed inside or outside of the function (local and global).

Examples:

• x = 600

def myfunc():

print(x)

myfunc()

print(x)

Output: 600

600

A variable created outside of a function is global and can be used by anyone.

• x = “Python”

def func5()

print(“Local Variable”, x)

func5

print(‘Global Variable’, x)

Output: Local Variable  Python

Global Variable  Python