input: 
  def expand_list(lst):
      """ Expand the given list by duplicating each element iteratively. However, due to
      the incorrect method of modifying the list during iteration, this function needs to
      be fixed.
      >>> expand_list([1, 2, 3])
      [1, 2, 3, 1, 2, 3, 1, 2, 3]
      >>> expand_list([0])
      [0, 0, 0, 0]
      """
  
output:     result = []
      for item in lst:
          result.extend([item] * (len(lst) + 1))
      return result