BLD: fix time module import conflict
See #3097.

Thanks for investigating this. I think it'd be better to replace the `import *` statement instead, though.

```
from cpython cimport (
        PyTypeObject,
        PyFloat_Check,
        PyObject_RichCompareBool,
        PyString_Check
)
```

seems to do the job.
If you can redo the commit, I'll merge it once travis passes.
 So should I change it then `git commit --amend`?
 yep. or just add another commit and I'll take care of it.
 Cool. Running the test suite on my machine and then I will push.
 In it goes. thanks.
