安装新的乌班图 下的 8.01版本，环境都装好了，到启动seahub的时候报错，
显示如下：
Error:Seahub failed to start.
Please try to run “./seahub.sh start” again
root@pili:/home/pili/seafile-server-8.0.1# ./seahub.sh start-fastcgi
LC_ALL is not set in ENV, set to en_US.UTF-8
Starting seahub (fastcgi) at 127.0.0.1:8000 …
Traceback (most recent call last):
File “/home/pili/seafile-server-8.0.1/seahub/manage.py”, line 10, in
execute_from_command_line(sys.argv)
File “/home/pili/seafile-server-8.0.1/seahub/thirdpart/django/core/management/init.py”, line 381, in execute_from_command_line
utility.execute()
File “/home/pili/seafile-server-8.0.1/seahub/thirdpart/django/core/management/init.py”, line 357, in execute
django.setup()
File “/home/pili/seafile-server-8.0.1/seahub/thirdpart/django/init.py”, line 24, in setup
apps.populate(settings.INSTALLED_APPS)
File “/home/pili/seafile-server-8.0.1/seahub/thirdpart/django/apps/registry.py”, line 91, in populate
app_config = AppConfig.create(entry)
File “/home/pili/seafile-server-8.0.1/seahub/thirdpart/django/apps/config.py”, line 90, in create
module = import_module(entry)
File “/usr/lib/python3.5/importlib/init.py”, line 126, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File “”, line 986, in _gcd_import
File “”, line 969, in _find_and_load
File “”, line 956, in _find_and_load_unlocked
ImportError: No module named ‘captcha’
Error:Seahub failed to start.
系统重装几次，版本换了两个也不行，一直卡在“Error:Seahub failed to start.”，实在不知道怎么办了！
