Coding in Python 12 – Local vs Global Variables

In video number 12 of the Coding in Python series, we explore the difference between local and global variables.

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Commands Used in this Video

An example of what not to do (this will fail!):

#!/usr/bin/env python3


def my_function():
    """ This is just a sample function.
    We're going to declare a variable in this function.
    """"
    message = "Hello everyone!"
    print(message)

my_function()

print(message)

Global variable example (fixes the problem from the previous code, notice the “global” line):

#!/usr/bin/env python3


def my_function():
    """ This is just a sample function.
    We're going to declare a variable in this function.
    """"
    global message
    message = "Hello everyone!"
    print(message)

my_function()

print(message)

Function (with a doc string):

#!/usr/bin/env python3

def my_function():
    """This is a doc string.
    This can be useful.
    It's pretty cool, isn't it?
    """
    mynum1 = 10
    mynum2 = 30
    print(mynum1 + mynum2)

my_function()
my_function()

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