input: from typing import List
  
  def remove_duplicates(list_of_integers: List[int]) -> List[int]:
      """ Removes all the duplicate elements from the given list of integers.
      >>> remove_duplicates([1, 2, 3, 2, 4, 5, 6, 3])
      [1, 2, 3, 4, 5, 6]
      """
output:     seen = set()
      result = []
      for num in list_of_integers:
          if num not in seen:
              seen.add(num)
              result.append(num)
      return result