@classmethod
def load(cls, warehouse, spec_id, adhoc_datasources=None):
    """Load a report from a spec ID

        Parameters
        ----------
        warehouse : Warehouse
            A zillion warehouse object
        spec_id : int
            A ReportSpec ID
        adhoc_datasources : list, optional
            A list of FieldManagers

        Returns
        -------
        Report

        """
    params = cls._load_params(spec_id)
    result = cls.from_params(warehouse, params, adhoc_datasources=
        adhoc_datasources)
    return result
