code: def r_annotation_body(self, sha):
          
          annotation = self.__queryinterface__.getResource(sha)
          if not annotation:
              return "invalid resource uri", 404
          # TODO this should inspect the annotation content
          # set appropriate Content-Type headers
          # and return the actual content
          content = annotation.read()
          if isinstance(content, Response):
              return content
          headers = {"Content-Type": annotation.mimetype}
          return Response(content, headers=headers)
docs: Route to retrieve contents of an annotation resource
  
          :param uri: The uri of the annotation resource
          :type uri: str
          :return: annotation contents
          :rtype: {str: Any}