I agree with Serhiy that !s solves the problem. But as a convenience it might be nice to add __format__. This issue pops up from time to time on Path and other types, and I don't think !s is very discoverable. Especially because formatting works with a specifier, but fails with one:

>>> format(path)
'/path/to/enlightenment'
>>> format(path, '>50')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: unsupported format string passed to PosixPath.__format__