pytest, parametrize, neasted list

[niski1996]

Hi, I tried to write little test:

li_1=([[1, 3, 2], [3, 5, 6]],[[2,6]])
li_der_1=[[2,6]]

@pytest.mark.parametrize("lite,expected",(li_1,li_der_1))
def test_der_li(lite,expected):
    assert der_li(lite)==expected

and I have problem:

Error:
platform win32 -- Python 3.7.7, pytest-5.4.1, py-1.8.1, pluggy-0.13.1 -- C:\Users\karol\anaconda3\envs\porjekt ostateczny\python.exe
cachedir: .pytest_cache
rootdir: C:\Users\karol\PycharmProjects\MES
collecting ... 
test_szczegolna_interpolacja_hermita.py:None (test_szczegolna_interpolacja_hermita.py)
test_szczegolna_interpolacja_hermita.py::test_der_li: in "parametrize" the number of names (2):
  ['lite', 'expected']
must be equal to the number of values (1):
  [[2, 6]]
collected 0 items / 1 error

How to pass these arguments corectly?