Can't use umlauts in filenames (API)

as described in issue #60 in seafile-server I can’t upload files with umlauts via the API and the python module requests. Because there is not that much feedback on github I thought I could write here. My code in essentially the same as in the webapi example for python.
Is somebody able to reproduce that or is it just my fault? What could be the reason for it?
Thanks to everybody trying to help me!

You could try to set a content type header.

That did not work out either. The problem here is about the filename not about the content, so I wondered how a content type header could help. But I tested it and it didn’t work.
I experimented a bit with requests and the seafile api. I can encode the filename a send in the data block in utf-8 but I can’t encode the path I use in open() because requests throws an error:"TypeError: a bytes-like object is required, not 'str'". It looks like seafile cares about the filename / path I use with open().