input: Write a function to get the third largest element in a given row. If the given row has fewer than three distinct elements, return None.
  
  
  def third_largest(lst):
      if len(lst) < 3:
          return None
      distinct = []
      for i in lst:
          if i not in distinct:
              distinct.append(i)
      if len(distinct) < 3:
          return None
      distinct.sort(reverse=True)
      return distinct[2]
  
  
  assert third_largest([12, 13, 13, 45, 22, 99])==22
  assert third_largest([1, 2, 3, 4, 5])==3
  assert third_largest([1, 1, 1, 1])==None
  assert third_largest([4, 5, 1, 2, 3])==3
  assert third_largest([10, 20, 30, 40, 50, 60])==40
  assert third_largest([5])==None
output: def third_largest(lst):
      if len(lst) < 3:
          return None
      distinct = []
      for i in lst:
          if i not in distinct:
              distinct.append(i)
      if len(distinct) < 3:
          return None
      distinct.sort(reverse=True)
      return distinct[2]