Programming 102: Binary search

number_list = [3, 8, 7, 9, 2, 1, 4]
number_list.sort()
print(number_list)

def binary_search(number_list, key):
    left = 0
    right = len(number_list)-1

    while left <= right:
        print (left, right)
        mid = int((right + left) / 2)
        print(mid)
        if number_list[mid] > key:
            right = mid - 1
        elif number_list[mid] < key:
            left = mid + 1
        else:
            return mid
    return False

key = int(input("What number are you looking for? "))
response = binary_search(number_list, key)

if response == False:
    print("Your value was not found!")
else:
    print("Your value was found!")