def METHOD_NAME(self):
    layer = FeaturePyramid(min_level=2, max_level=5)
    c2 = np.ones([2, 64, 64, 3])
    c3 = np.ones([2, 32, 32, 3])
    c4 = np.ones([2, 16, 16, 3])
    c5 = np.ones([2, 8, 8, 3])
    list_input = [c2, c3, c4, c5]
    with self.assertRaisesRegexp(
        ValueError, "expects input features to be a dict"
    ):
        layer(list_input)
    dict_input_with_missing_feature = {2: c2, 3: c3, 4: c4}
    with self.assertRaisesRegexp(
        ValueError, "Expect feature keys.*[2, 3, 4, 5]"
    ):
        layer(dict_input_with_missing_feature)