input: Write a Python function that duplicates a list from a tuple containing just one element.
  assert lcopy([1, 2, 3]) == [1, 2, 3]
  assert lcopy([4, 8, 2, 10, 15, 18]) == [4, 8, 2, 10, 15, 18]
  assert lcopy([4, 5, 6]) == [4, 5, 6]
output: def lcopy(t):
      return list(t[0])