code: def NEW_DEBUG_FRAME(self, requestHeader):
          
          if self.DEBUG_FLAG:  # pragma no branch (Flag always set in tests)
              new_frame = [requestHeader, None, None, None]
              if self._frameCount < self.DEBUG_FRAME_BUFFER_SIZE - 1:  # pragma no branch (Should be covered)
                  self._frameBuffer.append(new_frame)
              else:
                  self._frameBuffer[0] = new_frame  # pragma no cover (Should be covered)
  
              self._frameCount = len(self._frameBuffer) - 1
docs: Initialize a debug frame with requestHeader
          Frame count is updated and will be attached to respond header
          The structure of a frame: [requestHeader, statusCode, responseHeader, raw_data]
          Some of them may be None