def _check_default_rule(self):
        if not self.default_rule:
            raise RuntimeError("Can't call parse() on a Grammar that has no "
                               "default rule. Choose a specific rule instead, "
                               "like some_grammar['some_rule'].parse(...).")
Enable the datastore stub.
dataset/ETHPy150Open erikrose/parsimonious/parsimonious/grammar.py/Grammar._check_default_rule--crossover with--dataset/ETHPy150Open GoogleCloudPlatform/python-compat-runtime/appengine-compat/exported_appengine_sdk/google/appengine/ext/testbed/__init__.py/Testbed.init_datastore_v3_stub