input: def Fibonacci_up_to(limit: int) -> List[int]:
      """ Calculate the Fibonacci numbers up to the given limit.
      >>> Fibonacci_up_to(10)
      [0, 1, 1, 2, 3, 5, 8]
      >>> Fibonacci_up_to(20)
      [0, 1, 1, 2, 3, 5, 8, 13]
      """
output:     fib_sequence = [0, 1]
      while True:
          next_fib = fib_sequence[-1] + fib_sequence[-2]
          if next_fib > limit:
              break
          fib_sequence.append(next_fib)
      return fib_sequence