Using only Kohlshuetter feature produces TypeError

[mtlive]

When I use kohlshuetter feature alone, trying to extract a content produces this error:

Traceback (most recent call last):
 File "test.py", line 35, in <module>
   content = content_extractor.extract(r.content)
 File "dragnet\extractor.py", line 171, in extract
   return str_cast(b'\n'.join(blocks[ind].text for ind in np.flatnonzero(preds)))
TypeError: sequence item 0: expected a bytes-like object, str found

I changed
str_cast(b'\n'.join(blocks[ind].text for ind in np.flatnonzero(preds)))
to
str_cast('\n'.join(blocks[ind].text for ind in np.flatnonzero(preds)))
and the error disappeared.
Is it ok to do so?