input: 
  from typing import List
  
  def remove_duplicates(my_list: List[int]) -> List[int]:
      """ Remove duplicates from a given list and return the list.
      >>> remove_duplicates([1, 2, 3, 4, 3, 2, 1])
      [1, 2, 3, 4]
      """
      return list(dict.fromkeys(my_list))
  
output:     
      return list(dict.fromkeys(my_list))
  