How to trigger a funtion from another python file code example

Example 1: python use functions from another file

#If you want to import all functions from file... but you will still need to
#mention the file name:
import pizza
pizza.pizza_function()

#If you want to import every function but you dont want to mention file name:
from pizza import *
pizza.pizza_function()

Example 2: how to import functions from another python file

from file_name import function_name #do not include brackets or file types