def load(self, filename, create_if_missing=True):
        filename = Path(filename)
        if not filename.exists() and create_if_missing:
            self.load_pip_requirements()
            with filename.open("w") as f:
                f.write(yaml.dump(self.serialized, default_flow_style=False,
                                  encoding=None))
            self.filename = filename
            return self.save(filename)
        with filename.open() as f:
            for group, requirements in yaml.load(f.read()).items():
                for requirement in requirements:
                    self[group].add(Requirement.coerce(requirement))
        self.filename = filename
def _drop_schema(self, force_drop=False):
        """ Drops the schema"""
        connection = connections[get_tenant_database_alias()]
        has_schema = hasattr(connection, 'schema_name')
        if has_schema and connection.schema_name not in (self.schema_name, get_public_schema_name()):
            raise Exception("Can't delete tenant outside it's own schema or "
                            "the public schema. Current schema is %s."
                            % connection.schema_name)

        if has_schema and schema_exists(self.schema_name) and (self.auto_drop_schema or force_drop):
            self.pre_drop()
            cursor = connection.cursor()
            cursor.execute('DROP SCHEMA "%s" CASCADE' % self.schema_name)