Translate a project node into SQLQuery.
        :param node: a treebrd node
        :return: a SQLQuery object for the tree rooted at node

def project(self, node):
        """
        Translate a project node into SQLQuery.
        :param node: a treebrd node
        :return: a SQLQuery object for the tree rooted at node
        """
        child_object = self.translate(node.child)
        child_object.select_block = str(node.attributes)
        return child_object