Otherwise monkeypatching get confused and will not work and the tests will fail. An effort was made to use the six http_client always (both in tests and the interceptor) but this led to infinite recursion, so going for the lame fix here. The functionality has always worked (as long as six wasn't involved) this is just getting things working in tests.
If you wish to run the tests without those tests which speak to the internet (there are a few that validate that the intercept does not intercept), set the WSGI_INTERCEPT_SKIP_NETWORK environment variable to "True". Any other value or no value will mean that the network tests will run.