Overwrite the given query parameters.

        This is the same as :meth:`Queryable.set_query_params`,
        except it overwrites existing parameters individually
        whereas ``set_query_params`` deletes all existing key in
        ``query_params``.

def add_query_params(self, query_params):
        '''Overwrite the given query parameters.

        This is the same as :meth:`Queryable.set_query_params`,
        except it overwrites existing parameters individually
        whereas ``set_query_params`` deletes all existing key in
        ``query_params``.
        '''
        query_params = as_multi_dict(query_params)
        for k in query_params:
            self.query_params.pop(k, None)
            for v in query_params.getlist(k):
                self.query_params[k] = v
        self.apply_param_schema()
        return self