Creates op_pos for node from uid to colon

def uid_something_colon(self, node):
        """ Creates op_pos for node from uid to colon """
        node.op_pos = [
            NodeWithPosition(node.uid, (node.first_line, node.first_col))
        ]
        position = (node.body[0].first_line, node.body[0].first_col)
        last, first = self.operators[':'].find_previous(position)
        node.op_pos.append(NodeWithPosition(last, first))
        return last