Some tests contradict the conditions in the description, e.g., problem 75:

   """Write a function that returns true if the given number is the multiplication of 3 prime numbers
    and false otherwise.
    Knowing that (a) is less then 100. 
    Example:
    >>> is_multiply_prime(30)
    True
    30 = 2 * 3 * 5
    """

but there are tests with a>100.
For problem 129, there is a condition that Every integer in the range [1, N * N] inclusive appears exactly once on the cells of the grid. but some tests do not satisfy that. There are possibly more