input: def third_largest(lst):
      """Given a list of numbers, find and return the third largest distinct element.
      If the list has fewer than 3 distinct elements, return None.
      >>> third_largest([12, 13, 13, 45, 22, 99])
      22
      >>> third_largest([5, 5, 5, 5])
      
      >>> third_largest([1, 2])
      
      """
output:     if len(lst) < 3:
          return None
      distinct_elements = list(set(lst))
      distinct_elements.sort(reverse=True)
      if len(distinct_elements) < 3:
          return None
      return distinct_elements[2]