我收到异常InvalidURL：URL的URL带有下划线，但标签无效。我在2.11.1中遇到此问题。 URL看起来像这样https://p-q-r-dev.appspot.com/n_m。尽管以前相同的东西可以正常工作，但此URI是否有问题。谢谢！
return requests.get(request_url)
lib/python2.7/site-packages/requests/api.py", line 70, in get
lib/python2.7/site-packages/requests/api.py", line 56, in request
/lib/python2.7/site-packages/requests/sessions.py", line 461, in request
prep = self.prepare_request(req)
lib/python2.7/site-packages/requests/sessions.py", line 394, in prepare_request
hooks=merge_hooks(request.hooks, self.hooks),
lib/python2.7/site-packages/requests/models.py", line 294, in prepare
self.prepare_url(url, params)
lib/python2.7/site-packages/requests/models.py", line 363, in prepare_url
raise InvalidURL('URL has an invalid label.')
InvalidURL: URL has an invalid label.