input: from typing import List
  
  def removeDuplicates(array: List[int]) -> List[int]:
      """Remove duplicates from a list of integers using built-in functions.
      >>> removeDuplicates([1, 2, 2, 3, 4, 4, 5])
      [1, 2, 3, 4, 5]
      >>> removeDuplicates([1, 1, 1, 1, 1])
      [1]
      >>> removeDuplicates([])
      []
      """
      return list(dict.fromkeys(array))
output:     return list(dict.fromkeys(array))