Method __getitem__

tests/test_structures/test_instance_data.py:25–32

(self, item)

        return len(self.tmp)

    def __getitem__(self, item):
        if isinstance(item, int):
            if item >= len(self) or item < -len(self):  # type:ignore
                raise IndexError(f'Index {item} out of range!')
            else:
                # keep the dimension
                item = slice(item, None, len(self))
        return TmpObject(self.tmp[item])

    @staticmethod
    def cat(tmp_objs):