Python Programming | Executing Functions for List Elements

Introduction

In Python, it is common to need to execute a function for each element in a list. This can be done using a for loop, but it can be tedious to write out the loop every time. In this challenge, you will create a function that takes a list and a function as arguments and executes the function for each element in the list.

Skills Graph

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Execute Function for Each List Element

Problem

Write a function for_each(itr, fn) that takes a list itr and a function fn as arguments. The function should execute fn once for each element in itr.

Example

def print_square(num):
    print(num*num)

for_each([1, 2, 3], print_square) ## prints 1 4 9

In the example above, the for_each function is called with a list [1, 2, 3] and a function print_square. The print_square function is executed once for each element in the list, printing the square of each number.

Summary

In this challenge, you created a function that takes a list and a function as arguments and executes the function for each element in the list. This is a useful technique for applying a function to every element in a list without having to write out a for loop every time.

Execute Function for Each List Element | Challenge