我正在尝试在GAE中运行测试项目，但无法正常工作

Question

我正在按照直接从AppInventor网站（https://github.com/cghersi/UWPExamples/tree/master/SyncAntiPattern）安装GAE和python 2.7的说明进行操作，但是当我尝试运行测试项目时，该应用会显示：

class CommentedMap(MutableMapping, ordereddict, CommentedBase):
  File "C:\Python27\lib\abc.py", line 86, in __new__
    cls = super(ABCMeta, mcls).__new__(mcls, name, bases, namespace)
TypeError: Error when calling the metaclass bases
    Cannot create a consistent method resolution
order (MRO) for bases CommentedBase, ordereddict, MutableMapping
2019-07-11 22:02:52 (Process exited with code 1)

我该怎么办？