I'm not sure it makes sense to submit this upstream - it fixes a bug introduced entirely by the fact that we're relocating the script with:

```ruby
bin.env_script_all_files(libexec+'bin', :PYTHONPATH => ENV['PYTHONPATH'])
```

While it would be nice for their code to be more durable in this respect, I doubt it'll happen.

So, okay, I'll use `inreplace` instead, then :)