input: Write a python function to remove an item from a list if it exists using the remove method.
  assert removeItem([2, 3, 4], 4) == [2, 3]
  assert removeItem([1, 5, 6, 7], 5) == [1, 6, 7]
  assert removeItem([10, 20, 30], 25) == [10, 20, 30]
output: def removeItem(lst, item):
      if item in lst:
          lst.remove(item)
      return lst