code: def desc(self):
          
          doc = None
          def visit_FunctionDef(node):
              """ https://docs.python.org/2/library/ast.html#ast.NodeVisitor.visit """
              if node.name != self.method_name:
                  return
  
              doc = ast.get_docstring(node)
              raise StopIteration(doc if doc else "")
  
          target = self.controller.controller_class
          try:
              node_iter = ast.NodeVisitor()
              node_iter.visit_FunctionDef = visit_FunctionDef
              node_iter.visit(ast.parse(inspect.getsource(target)))
  
          except StopIteration as e:
              doc = str(e)
  
          if not doc: doc = ""
          return doc
docs: return the description of this endpoint