code: def add_special_file(self, mask, path, from_quick_server, ctype=None):
          
          full_path = path if not from_quick_server else os.path.join(
              os.path.dirname(__file__), path)
  
          def read_file(_req, _args):
              with open(full_path, 'rb') as f_out:
                  return Response(f_out.read(), ctype=ctype)
  
          self.add_text_get_mask(mask, read_file)
          self.set_file_argc(mask, 0)
docs: Adds a special file that might have a different actual path than
             its address.
  
          Parameters
          ----------
          mask : string
              The URL that must be matched to perform this request.
  
          path : string
              The actual file path.
  
          from_quick_server : bool
              If set the file path is relative to *this* script otherwise it is
              relative to the process.
  
          ctype : string
              Optional content type.