input: Write a python function to remove duplicates from a list.
  assert removeDuplicates([1, 2, 2, 3, 4, 4, 5]) == [1, 2, 3, 4, 5]
  assert removeDuplicates([10, 10, 20, 30, 30, 40]) == [10, 20, 30, 40]
  assert removeDuplicates([5, 5, 5, 5, 5]) == [5]
output: def removeDuplicates(lst):
      return list(dict.fromkeys(lst))