input: Write a function to remove duplicates from a list.
  assert removeDuplicates([1, 2, 2, 3, 4, 4, 5]) == [1, 2, 3, 4, 5]
  assert removeDuplicates([5, 5, 5, 5, 5]) == [5]
  assert removeDuplicates([1, 2, 3, 4, 5]) == [1, 2, 3, 4, 5]
  assert removeDuplicates([]) == []
  assert removeDuplicates([1, 1, 2, 3, 3, 3, 4]) == [1, 2, 3, 4]
output: def removeDuplicates(lst):
      return list(dict.fromkeys(lst))