like I already commented on GitHub issues couple of minutes ago:
Problem is caused by olded urllib3 version not from chardet. Update your urlib modules to work with chardet 3.0.4
These are my thirdpart modules:
root@hiperborea /home/seafile/seafile-server-latest/seahub/thirdpart # cat easy-install.pth
./chardet-3.0.4-py2.7.egg #### you can see 3.0.4!
./Django-1.11.13-py2.7.egg
./django_compressor-2.2-py2.7.egg
./django_formtools-2.1-py2.7.egg
./django_post_office-3.0.4-py2.7.egg
./djangorestframework-3.8.2-py2.7.egg
./django_simple_captcha-0.5.7-py2.7.egg
./django_statici18n-1.8.0-py2.7.egg
./gunicorn-19.8.1-py2.7.egg
./python_memcached-1.59-py2.7.egg
./pytz-2018.4-py2.7.egg
./qrcode-5.3-py2.7.egg
./requests-2.18.4-py2.7.egg
./requests_oauthlib-0.8.0-py2.7.egg
./six-1.11.0-py2.7.egg
./openpyxl-2.5.3-py2.7.egg
./django_webpack_loader-0.6.0-py2.7.egg
./setuptools-39.2.0-py2.7.egg
./jsonfield-2.0.2-py2.7.egg
./django_appconf-1.0.2-py2.7.egg
./et_xmlfile-1.0.1-py2.7.egg
./certifi-2018.4.16-py2.7.egg
./oauthlib-2.1.0-py2.7.egg
./django_ranged_response-0.2.0-py2.7.egg
./django_constance-2.1.0-py2.7.egg
./flup-1.0.2-py2.7.egg
./python_dateutil-2.7.3-py2.7.egg
./idna-2.6-py2.7.egg
./rcssmin-1.0.6-py2.7-linux-armv6l.egg
./rjsmin-1.0.12-py2.7-linux-armv6l.egg
./olefile-0.45.1-py2.7.egg
./jdcal-1.4-py2.7.egg
./django_picklefield-1.0.0-py2.7.egg
./captcha-0.2.4-py2.7.egg
solution is update urlib to meet chardet dependencies. I think someone has posted the solution a couple of days ago. wait… I will search for the post and i come back to you …
ok, I found it:
the solution was provided by @klangborste we should thank to him 