# returns a boolean value if number is even
def is_even(number: int):
    # make negative number positive
    if number < 0:
        number = number * -1
        
    # keep subtracting 2 to the number
    for i in range(number, -1, -2):
        # if 0 is reached, number must be even
        if i == 0:
            return True
            
    # 0 wasn't reached in the above loop, therefore number is odd
    return False 

print(is_even(0))
print(is_even(-1))
print(is_even(-4))
print(is_even(1))
print(is_even(4))
print(is_even(5))
print(is_even(2))
print(is_even(-5))
print(is_even(-2))