input: from typing import List
  
  
  def remove_duplicates(numbers: List[int]) -> List[int]:
      """ From a list of integers, remove all elements that occur more than once.
      Keep order of elements left the same as in the input.
      >>> remove_duplicates([1, 2, 3, 2, 4])
      [1, 3, 4]
      """
  
output:     seen = set()
      result = []
      for num in numbers:
          if numbers.count(num) == 1:
              result.append(num)
          elif num not in seen:
              seen.add(num)
              result.append(num)
      return result