for i in range(1, len(x_list)):

    if y_list[i] - y_list[i-1] < 0:
        return False

return True

if name == '__main__':

x_list = [0, 1.2, 3.4, 5.6]
y_list = [3.1, 2.9, 2.7, 2.5]

print(checkMonotonicIncreasing(x_list=x_list, y_list=y_list))