Traceback (most recent call last):


 "/var/local/pyweb/virtualenv/dnsalloc/lib/python2.7/site-packages/django/core/handlers/base.py", line 132, in get_response

response = wrapped_callback(request, *callback_args, **callback_kwargs)


 "/var/local/pyweb/virtualenv/dnsalloc/lib/python2.7/site-packages/django/contrib/admin/options.py", line 618, in wrapper

return self.admin_site.admin_view(view)(*args, **kwargs)


 "/var/local/pyweb/virtualenv/dnsalloc/lib/python2.7/site-packages/django/utils/decorators.py", line 110, in _wrapped_view

response = view_func(request, *args, **kwargs)


 "/var/local/pyweb/virtualenv/dnsalloc/lib/python2.7/site-packages/django/views/decorators/cache.py", line 57, in _wrapped_view_func

response = view_func(request, *args, **kwargs)


 "/var/local/pyweb/virtualenv/dnsalloc/lib/python2.7/site-packages/django/contrib/admin/sites.py", line 233, in inner

return view(request, *args, **kwargs)


 "/var/local/pyweb/virtualenv/dnsalloc/lib/python2.7/site-packages/django_celery_beat/admin.py", line 136, in changelist_view

extra_context['wrong_scheduler'] = not is_database_scheduler(scheduler)


 "/var/local/pyweb/virtualenv/dnsalloc/lib/python2.7/site-packages/django_celery_beat/utils.py", line 41, in is_database_scheduler

return issubclass(symbol_by_name(scheduler), DatabaseScheduler)
TypeError: issubclass() arg 1 must be a class

Traceback (most recent call last):


 "C:\Users\S10500\AppData\Local\Continuum\anaconda3\lib\site-packages\spyder\widgets\ipythonconsole\client.py", line 575, in show_time

elapsed_time = time.monotonic() - self.t0
TypeError: unsupported operand type(s) for -: 'float' and 'NoneType'
