input: 
  def find_maximum(numbers: List[int]) -> int:
      """
      Find the maximum element in the given list of numbers.
      >>> find_maximum([1, 43, 78, 3, 92, 42])
      92
      """
  
output:     if not numbers:
          return None
      max_num = numbers[0]
      for num in numbers:
          if num > max_num:
              max_num = num
      return max_num