input: Write a python function to filter out non-integer values from a list.
  assert filter_non_integers([1, 2, 3, "a", "b", "c", 4, 5])==["a", "b", "c"]
  assert filter_non_integers([10, "hello", 30, "world", 50])==["hello", "world"]
  assert filter_non_integers([7, 8, "x", "y", 9])==["x", "y"]
output: def filter_non_integers(lst):
      return [x for x in lst if not isinstance(x, int)]