code: def _get_input_validator(self, request):
          
  
          method = request.method.upper()
          if method != 'POST':
              return self.representation
          elif self.post_representation:
              return self.post_representation
          else:
              return self.representation
docs: Return appropriate input validator.
  
          For POST requests, ``self.post_representation`` is returned
          if it is present, ``self.representation`` otherwise.