code: def add_comment(self, body, allow_create=False, allow_hashes=False,
                      summary=None):
          "Implement as required by parent to store comment in CSV file."
  
          if allow_hashes:
              raise ValueError('allow_hashes not implemented for %s yet' % (
                  self.__class__.__name__))
          if self.thread_id is None:
              self.thread_id = self.lookup_thread_id()
          if not os.path.exists(self.thread_id):
              if not allow_create:
                  raise KeyError(self.topic)
              with open(self.thread_id, 'a', newline='') as fdesc:
                  csv.writer(fdesc).writerow(self.header)
  
          with open(self.thread_id, 'a', newline='') as fdesc:
              writer = csv.writer(fdesc)
              writer.writerow([self.user, datetime.datetime.utcnow(), summary,
                               body, '']f add_comment(self, body, allow_create=False, allow_hashes=False,
                      summary=None):
          "Implement as required by parent to store comment in CSV file."
  
          if allow_hashes:
              raise ValueError('allow_hashes not implemented for %s yet' % (
                  self.__class__.__name__))
          if self.thread_id is None:
              self.thread_id = self.lookup_thread_id()
          if not os.path.exists(self.thread_id):
              if not allow_create:
                  raise KeyError(self.topic)
              with open(self.thread_id, 'a', newline='') as fdesc:
                  csv.writer(fdesc).writerow(self.header)
  
          with open(self.thread_id, 'a', newline='') as fdesc:
              writer = csv.writer(fdesc)
              writer.writerow([self.user, datetime.datetime.utcnow(), summary,
                               body, ''])
docs: Implement as required by parent to store comment in CSV file.