input: 
  from typing import List
  
  def find_largest_three_numbers(numbers: List[int]) -> List[int]:
      """Find the largest three numbers in a given list.
      >>> find_largest_three_numbers([1, 6, 3, 8, 7, 4])
      [6, 7, 8]
      >>> find_largest_three_numbers([9, 1, 5, 3, 8, 2])
      [5, 8, 9]
      """
  
output:     if len(numbers) < 3:
          return sorted(numbers, reverse=True)
      
      largest_three = sorted(numbers[:3])
      
      for num in numbers[3:]:
          if num > largest_three[0]:
              largest_three[0] = num
              largest_three.sort()
      
      return sorted(largest_three, reverse=True)