def select_projects(self, *args):
        """Copy the query and add filtering by monitored projects.

        This is only useful if the target project represents a Stackdriver
        account containing the specified monitored projects.

        Examples::

            query = query.select_projects('project-1')
            query = query.select_projects('project-1', 'project-2')

        :type args: tuple
        :param args: Project IDs limiting the resources to be included
            in the query.

        :rtype: :class:`Query`
        :returns: The new query object.
        """
        new_query = copy.deepcopy(self)
        new_query._filter.projects = args
        return new_query