def METHOD_NAME(self) -> Generator["defer.Deferred[object]", object, None]:
    self.mock_txn.rowcount = 1
    yield defer.ensureDeferred(
        self.datastore.db_pool.simple_update_one(
            table="tablename",
            keyvalues={"keycol": "TheKey"},
            updatevalues={"columnname": "New Value"},
        )
    )
    self.mock_txn.execute.assert_called_with(
        "UPDATE tablename SET columnname = ? WHERE keycol = ?",
        ["New Value", "TheKey"],
    )