input: 
  def find_largest_number(lst: List[int]) -> int:
      """
      Find the largest number in the given list.
      >>> find_largest_number([1000, 506, 299, 620, 35])
      1000
      """
  
output:     if not lst:
          return None
      max_num = lst[0]
      for num in lst:
          if num > max_num:
              max_num = num
      return max_num