'Method loads the role from the DB based on the given role id.
:param  decoded_role_id:      id of the role to load from the DB
:type   decoded_role_id:      int
:returns:   the loaded Role object
:rtype:     galaxy.model.Role
:raises: InconsistentDatabase, RequestParameterInvalidException, InternalServerError'

def get(self, trans, decoded_role_id):

    try:
        role = self.session().query(self.model_class).filter((self.model_class.id == decoded_role_id)).one()
    except sqlalchemy_exceptions.MultipleResultsFound:
        raise galaxy.exceptions.InconsistentDatabase('Multiple    roles    found    with    the    same    id.')
    except sqlalchemy_exceptions.NoResultFound:
        raise galaxy.exceptions.RequestParameterInvalidException('No    role    found    with    the    id    provided.')
    except Exception as e:
        raise galaxy.exceptions.InternalServerError(('Error    loading    from    the    database.' + str(e)))
    return role
