Return a slice object to slice a list/bytearray by.

        Positional arguments:
        index -- index of self.SIGNATURE to target self.bytearray by.

        Returns:
        slice() object. E.g. `x = _get_slicers(0); ba_instance[x]`

def _get_slicers(self, index):
        """Return a slice object to slice a list/bytearray by.

        Positional arguments:
        index -- index of self.SIGNATURE to target self.bytearray by.

        Returns:
        slice() object. E.g. `x = _get_slicers(0); ba_instance[x]`
        """
        if not index:  # first item.
            return slice(0, self.SIGNATURE[0])
        if index >= len(self.SIGNATURE):
            raise IndexError('index out of self.SIGNATURE range')
        pad_start = sum(self.SIGNATURE[:index])
        pad_stop = pad_start + self.SIGNATURE[index]
        return slice(pad_start, pad_stop)