human
I wrote the below code

    if (test_dtypes is None):
        test_dtypes = sparse.all_dtypes
    class Tester(unittest.TestCase, ):
        def setUp(self):
            super(Tester, self).setUp()
            self.op = op
            self.expected_f = expected_f
            self.gap = gap
            if (gap_grad is not None):
                self.gap_grad = gap_grad
            else:
                self.gap_grad = gap
            utt.seed_rng()
            assert (eval(self.__class__.__name__) is self.__class__)
        def test_op(self):
            for format in sparse.sparse_formats:
                for dtype in test_dtypes:
                    if ((dtype == 'int8') or (dtype == 'uint8')):
                        continue
                    if dtype.startswith('uint'):
                        if (self.gap and (len(self.gap) == 2) and (self.gap[0] < 0)):
                            if (self.gap[1] >= 1):
                                self.gap = (0, self.gap[1])
                            else:
                                raise TypeError('Gap    not    suitable    for', dtype, self.__name__)
                    (variable, data) = sparse_random_inputs(format, shape=(4, 7), out_dtype=dtype, gap=self.gap)
                    f = theano.function(variable, self.op(*variable))
                    tested = f(*data)
                    data = [m.toarray() for m in data]
                    expected = self.expected_f(*data)
                    assert (tested.format == format)
                    tested = tested.toarray()
                    try:
                        utt.assert_allclose(expected, tested)
                    except AssertionError:
                        raise AssertionError(self.__name__)
                for dtype in ['int8', 'uint8']:
                    if (dtype in test_dtypes):
                        if self.gap:
                            domain = self.gap
                            if (dtype == 'uint8'):
                                if ((len(domain) == 2) and (domain[0] < 0)):
                      ...

What's a good function header?
 ... Here's a good function header?
assistant
#Here's a good function header.

def elemwise_checker(op, expected_f, gap=None, test_dtypes=None, grad_test=True, name=None, gap_grad=None):