def itransform(self, seq):
if self is not identity and self != identity:<EOL><INDENT>sa, sb, sc, sd, se, sf, _, _, _ = self<EOL>for i, (x, y) in enumerate(seq):<EOL><INDENT>seq[i] = (x * sa + y * sd + sc, x * sb + y * se + sf)<EOL><DEDENT><DEDENT>
Transform a sequence of points or vectors in place.

        :param seq: Mutable sequence of :class:`~planar.Vec2` to be
            transformed.
        :returns: None, the input sequence is mutated in place.