code: def run_query(self, query):
          
          collection = self.ds.connection(self.collection_name)
  
          cursor = collection.find(query)
          if cursor.count() == 0:
              raise LookupError('Collection {0} has no {1} records'
                                .format(self.collection_name, self.model_klass.__name__))
          return [self.model_klass.from_json(entry) for entry in cursor]
docs: method runs query on a specified collection and return a list of filtered Model records