Return whether an input number is even or odd

Write a function that will take in a number, and return whether it's even or odd.

even_or_odd(57) == 'odd'
even_or_odd(2422) == 'even'

Test Cases

test with odd number - Run Test

def test_with_odd_number():
    assert even_or_odd(17) == 'odd'

test with even number - Run Test

def test_with_even_number():
    assert even_or_odd(42) == 'even'