RPI 7.0.5 Error:Seahub failed to start

hi,
i cant start seahub,i get this error:
./seahub.sh start-fastcgi 8000

LC_ALL is not set in ENV, set to en_US.UTF-8
./seahub.sh: Zeile 208: Warnung: setlocale: LC_ALL: Kann die Locale nicht ändern (en_US.UTF-8): Datei oder Verzeichnis nicht gefunden
Starting seahub (fastcgi) at 127.0.0.1:8000 …
Traceback (most recent call last):
File “/home/pi/seafile-rpi/seafile-server-7.0.5/seahub/manage.py”, line 10, in
execute_from_command_line(sys.argv)
File “/home/pi/seafile-rpi/seafile-server-7.0.5/seahub/thirdpart/Django-1.11.15-py2.7.egg/django/core/management/init.py”, line 364, in execute_from_command_line
utility.execute()
File “/home/pi/seafile-rpi/seafile-server-7.0.5/seahub/thirdpart/Django-1.11.15-py2.7.egg/django/core/management/init.py”, line 338, in execute
django.setup()
File “/home/pi/seafile-rpi/seafile-server-7.0.5/seahub/thirdpart/Django-1.11.15-py2.7.egg/django/init.py”, line 27, in setup
apps.populate(settings.INSTALLED_APPS)
File “/home/pi/seafile-rpi/seafile-server-7.0.5/seahub/thirdpart/Django-1.11.15-py2.7.egg/django/apps/registry.py”, line 85, in populate
app_config = AppConfig.create(entry)
File “/home/pi/seafile-rpi/seafile-server-7.0.5/seahub/thirdpart/Django-1.11.15-py2.7.egg/django/apps/config.py”, line 94, in create
module = import_module(entry)
File “/usr/lib/python2.7/importlib/init.py”, line 37, in import_module
import(name)
File “/home/pi/seafile-rpi/seafile-server-7.0.5/seahub/thirdpart/django_post_office-3.0.4-py2.7.egg/post_office/init.py”, line 3, in
from .backends import EmailBackend
File “/home/pi/seafile-rpi/seafile-server-7.0.5/seahub/thirdpart/django_post_office-3.0.4-py2.7.egg/post_office/backends.py”, line 4, in
from .settings import get_default_priority
File “/home/pi/seafile-rpi/seafile-server-7.0.5/seahub/thirdpart/django_post_office-3.0.4-py2.7.egg/post_office/settings.py”, line 95, in
context_field_class = import_attribute(CONTEXT_FIELD_CLASS)
File “/home/pi/seafile-rpi/seafile-server-7.0.5/seahub/thirdpart/django_post_office-3.0.4-py2.7.egg/post_office/compat.py”, line 45, in import_attribute
module = importlib.import_module(module_name)
File “/usr/lib/python2.7/importlib/init.py”, line 37, in import_module
import(name)
File “/home/pi/seafile-rpi/seafile-server-7.0.5/seahub/thirdpart/jsonfield-3.1.0-py2.7.egg/jsonfield/init.py”, line 1, in
File “/home/pi/seafile-rpi/seafile-server-7.0.5/seahub/thirdpart/jsonfield-3.1.0-py2.7.egg/jsonfield/fields.py”, line 28
def init(self, *args, dump_kwargs=None, load_kwargs=None, **kwargs):
^
SyntaxError: invalid syntax
Error:Seahub failed to start.

can you help me pleaese ?

@bambam Which OS Distribution and which HW do you use?