Traceback (most recent call last):


 "C:\Users\adnan\AppData\Local\Programs\Python\Python38-32\lib\site-packages\tornado\ioloop.py", line 907, in _run

return self.callback()


 "C:\Users\adnan\AppData\Local\Programs\Python\Python38-32\lib\site-packages\distributed\nanny.py", line 414, in memory_monitor

process = self.process.process
AttributeError: 'NoneType' object has no attribute 'process'

Traceback (most recent call last):


 "/Users/yan/PycharmProjects/my_project/venv/lib/python3.7/site-packages/django/core/handlers/exception.py", line 34, in inner

response = get_response(request)


 "/Users/yan/PycharmProjects/my_project/venv/lib/python3.7/site-packages/django/core/handlers/base.py", line 115, in _get_response

response = self.process_exception_by_middleware(e, request)


 "/Users/yan/PycharmProjects/my_project/venv/lib/python3.7/site-packages/django/core/handlers/base.py", line 113, in _get_response

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


 "/Users/yan/PycharmProjects/my_project/venv/lib/python3.7/site-packages/django/contrib/admin/options.py", line 607, in wrapper

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


 "/Users/yan/PycharmProjects/my_project/venv/lib/python3.7/site-packages/django/utils/decorators.py", line 130, in _wrapped_view

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


 "/Users/yan/PycharmProjects/my_project/venv/lib/python3.7/site-packages/django/views/decorators/cache.py", line 44, in _wrapped_view_func

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


 "/Users/yan/PycharmProjects/my_project/venv/lib/python3.7/site-packages/django/contrib/admin/sites.py", line 231, in inner

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


 "/Users/yan/PycharmProjects/my_project/venv/lib/python3.7/site-packages/django/contrib/admin/options.py", line 1638, in add_view

return self.changeform_view(request, None, form_url, extra_context)


 "/Users/yan/PycharmProjects/my_project/venv/lib/python3.7/site-packages/django/utils/decorators.py", line 43, in _wrapper

return bound_method(*args, **kwargs)


 "/Users/yan/PycharmProjects/my_project/venv/lib/python3.7/site-packages/django/utils/decorators.py", line 130, in _wrapped_view

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


 "/Users/yan/PycharmProjects/my_project/venv/lib/python3.7/site-packages/django/contrib/admin/options.py", line 1522, in changeform_view

return self._changeform_view(request, object_id, form_url, extra_context)


 "/Users/yan/PycharmProjects/my_project/venv/lib/python3.7/site-packages/django/contrib/admin/options.py", line 1558, in _changeform_view

form_validated = form.is_valid()


 "/Users/yan/PycharmProjects/my_project/venv/lib/python3.7/site-packages/django/forms/forms.py", line 180, in is_valid

return self.is_bound and not self.errors


 "/Users/yan/PycharmProjects/my_project/venv/lib/python3.7/site-packages/django/forms/forms.py", line 175, in errors

self.full_clean()


 "/Users/yan/PycharmProjects/my_project/venv/lib/python3.7/site-packages/django/forms/forms.py", line 378, in full_clean

self._post_clean()


 "/Users/yan/PycharmProjects/my_project/venv/lib/python3.7/site-packages/django/forms/models.py", line 404, in _post_clean

self.instance.full_clean(exclude=exclude, validate_unique=False)


 "/Users/yan/PycharmProjects/my_project/venv/lib/python3.7/site-packages/django/db/models/base.py", line 1200, in full_clean

self.clean_fields(exclude=exclude)


 "/Users/yan/PycharmProjects/my_project/venv/lib/python3.7/site-packages/django/db/models/base.py", line 1242, in clean_fields

setattr(self, f.attname, f.clean(raw_value, self))


 "/Users/yan/PycharmProjects/my_project/venv/lib/python3.7/site-packages/django/db/models/fields/__init__.py", line 648, in clean

value = self.to_python(value)


 "/Users/yan/PycharmProjects/my_project/venv/lib/python3.7/site-packages/djongo/models/fields.py", line 242, in to_python

f'Value: {value} must be an instance of {self.base_type}')


 "/Users/yan/PycharmProjects/my_project/venv/lib/python3.7/site-packages/django/db/models/base.py", line 521, in __str__

return '%s object (%s)' % (self.__class__.__name__, self.pk)


 "/Users/yan/PycharmProjects/my_project/venv/lib/python3.7/site-packages/django/db/models/base.py", line 568, in _get_pk_val

return getattr(self, meta.pk.attname)
AttributeError: 'NoneType' object has no attribute 'attname'
