code: def _call_middlewares(self):
          ''' Execute the middleware stack '''
          for middleware in self.middlewares:
              if self._check_condition(middleware['when']):
                  self._call_one_middleware(middlewaref _call_middlewares(self):
          ''' Execute the middleware stack '''
          for middleware in self.middlewares:
              if self._check_condition(middleware['when']):
                  self._call_one_middleware(middleware)
docs: Execute the middleware stack