Error with `import pip` in pip 9.0.2

Some users are now experiencing an import error when calling import pip in a function with pip 9.0.2. Downgrading to 9.0.1 fixes the issue.

Trace: https://user-images.githubusercontent.com/2273226/37558391-5e41fc94-2a24-11e8-9fdc-5884445e829a.png

More details here: https://github.com/Miserlou/Zappa/issues/1446

[Miserlou]

Yes, this is the type of change that people could expect from a MAJOR version update. That would be fine.

Unfortunately, this massive change came in a PATCH update, which is supposed to fix things, not break them. This is the exact opposite of semantic versioning. And, as a result, we are seeing massive damage across the Python ecosystem.

You should revert this change ASAP in another PATCH update, then have the major breaking change come with the MAJOR version update. Now that you’ve already broken everything for everybody prematurely, I think they will be more aware that the actual major change is coming.

I also think it’s a cop out to say that this was documented and announced already, considering that it was not documented in the stable documentation, and that the announcement said that the break would happen for the major version, not for in a patch a month prior.

Please, just save everybody a massive headache, revert this problem and start actually adhering to semantic versioning.

[Miserlou]

Come on… making a huge breaking change in a single x.x.PATCH version bump? For a top level method that’s called “main”? I think that’s pretty poor form…