Could you rewrite this and the lines below by importing only what you need from the top-level package, i.e.:

```
from honcho import ON_POSIX, ON_WINDOWS
...
if ON_WINDOWS:
   ...
```

This makes it far easier to avoid circular dependencies if we ever want to import things from `honcho.command` into the top level package.

Alternatively, you could move the two `ON_FOO` lines into, say, `honcho/compat.py` and import them from there. Whichever you prefer.