How to use the cerberus.utils.mapping_hash function in Cerberus

def validate(self, schema=None):
        if schema is None:
            schema = self.schema
        _hash = (mapping_hash(schema), mapping_hash(self.validator.types_mapping))
        if _hash not in self.validator._valid_schemas:
            self._validate(schema)
            self.validator._valid_schemas.add(_hash)

def validate(self, schema=None):
        """ Validates a schema that defines rules against supported rules.

        :param schema: The schema to be validated as a legal cerberus schema
                       according to the rules of the assigned Validator object.
                       Raises a :class:`~cerberus.base.SchemaError` when an invalid
                       schema is encountered. """
        if schema is None:
            schema = self.schema
        _hash = (mapping_hash(schema), mapping_hash(self.validator.types_mapping))
        if _hash not in self.validator._valid_schemas:
            self._validate(schema)
            self.validator._valid_schemas.add(_hash)

def _check_with_bulk_schema(self, field, value):
        # resolve schema registry reference
        if isinstance(value, _str_type):
            if value in self.known_rules_set_refs:
                return
            else:
                self.known_rules_set_refs.add(value)
            definition = self.target_validator.rules_set_registry.get(value)
            if definition is None:
                self._error(field, 'Rules set definition %s not found.' % value)
                return
            else:
                value = definition

        _hash = (
            mapping_hash({'turing': value}),
            mapping_hash(self.target_validator.types_mapping),
        )
        if _hash in self.target_validator._valid_schemas:
            return

        validator = self._get_child_validator(
            document_crumb=field,
            allow_unknown=False,
            schema=self.target_validator.rules,
        )
        validator(value, normalize=False)
        if validator._errors:
            self._error(validator._errors)
        else:
            self.target_validator._valid_schemas.add(_hash)

def _validate_logical(self, rule, field, value):
        """ {'allowed': ('allof', 'anyof', 'noneof', 'oneof')} """
        if not isinstance(value, Sequence):
            self._error(field, errors.BAD_TYPE)
            return

        validator = self._get_child_validator(
            document_crumb=rule,
            allow_unknown=False,
            schema=self.target_validator.validation_rules,
        )

        for constraints in value:
            _hash = (
                mapping_hash({'turing': constraints}),
                mapping_hash(self.target_validator.types_mapping),
            )
            if _hash in self.target_validator._valid_schemas:
                continue

            validator(constraints, normalize=False)
            if validator._errors:
                self._error(validator._errors)
            else:
                self.target_validator._valid_schemas.add(_hash)

def _validator_bulk_schema(self, field, value):
        # resolve schema registry reference
        if isinstance(value, _str_type):
            if value in self.known_rules_set_refs:
                return
            else:
                self.known_rules_set_refs += (value,)
            definition = self.target_validator.rules_set_registry.get(value)
            if definition is None:
                self._error(field, 'Rules set definition %s not found.' % value)
                return
            else:
                value = definition

        _hash = (
            mapping_hash({'turing': value}),
            mapping_hash(self.target_validator.types_mapping),
        )
        if _hash in self.target_validator._valid_schemas:
            return

        validator = self._get_child_validator(
            document_crumb=field,
            allow_unknown=False,
            schema=self.target_validator.rules,
        )
        validator(value, normalize=False)
        if validator._errors:
            self._error(validator._errors)
        else:
            self.target_validator._valid_schemas.add(_hash)

# resolve schema registry reference
        if isinstance(value, _str_type):
            if value in self.known_rules_set_refs:
                return
            else:
                self.known_rules_set_refs += (value,)
            definition = self.target_validator.rules_set_registry.get(value)
            if definition is None:
                self._error(field, 'Rules set definition %s not found.' % value)
                return
            else:
                value = definition

        _hash = (
            mapping_hash({'turing': value}),
            mapping_hash(self.target_validator.types_mapping),
        )
        if _hash in self.target_validator._valid_schemas:
            return

        validator = self._get_child_validator(
            document_crumb=field,
            allow_unknown=False,
            schema=self.target_validator.rules,
        )
        validator(value, normalize=False)
        if validator._errors:
            self._error(validator._errors)
        else:
            self.target_validator._valid_schemas.add(_hash)