Traceback (most recent call last):


 "/home/ezimir/test-eshop/lib/python3.9/site-packages/django/core/handlers/exception.py", line 47, in inner

response = get_response(request)


 "/home/ezimir/test-eshop/lib/python3.9/site-packages/django/core/handlers/base.py", line 181, in _get_response

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


 "/home/ezimir/test-eshop/lib/python3.9/site-packages/django/contrib/auth/decorators.py", line 21, in _wrapped_view

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


 "/home/ezimir/test-eshop/lib/python3.9/site-packages/django/views/generic/base.py", line 70, in view

return self.dispatch(request, *args, **kwargs)


 "/home/ezimir/test-eshop/lib/python3.9/site-packages/django/views/generic/base.py", line 98, in dispatch

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


 "/home/ezimir/test-eshop/lib/python3.9/site-packages/django/views/generic/edit.py", line 172, in post

return super().post(request, *args, **kwargs)


 "/home/ezimir/test-eshop/lib/python3.9/site-packages/django/views/generic/edit.py", line 142, in post

return self.form_valid(form)


 "/home/ezimir/test-eshop/lib/python3.9/site-packages/django/views/generic/edit.py", line 125, in form_valid

self.object = form.save()


 "/home/ezimir/test-eshop/lib/python3.9/site-packages/treebeard/forms.py", line 145, in save

self.instance.move(reference_node, pos=position_type)


 "/home/ezimir/test-eshop/lib/python3.9/site-packages/treebeard/mp_tree.py", line 1164, in move

return MP_MoveHandler(self, target, pos).process()


 "/home/ezimir/test-eshop/lib/python3.9/site-packages/treebeard/mp_tree.py", line 473, in process

if self.target.is_descendant_of(self.node):
AttributeError: 'NoneType' object has no attribute 'is_descendant_of'


Traceback (most recent call last):



 "/usr/lib/python3.7/runpy.py", line 193, in _run_module_as_main


"__main__", mod_spec)



 "/usr/lib/python3.7/runpy.py", line 85, in _run_code


exec(code, run_globals)



 "/usr/local/lib/python3.7/dist-packages/pip/__main__.py", line 26, in <module>


sys.exit(_main())



 "/usr/local/lib/python3.7/dist-packages/pip/_internal/cli/main.py", line 73, in main


command = create_command(cmd_name, isolated=("--isolated" in cmd_args))



 "/usr/local/lib/python3.7/dist-packages/pip/_internal/commands/__init__.py", line 104, in create_command


module = importlib.import_module(module_path)



 "/usr/lib/python3.7/importlib/__init__.py", line 127, in import_module


return _bootstrap._gcd_import(name[level:], package, level)



 "<frozen importlib._bootstrap>", line 1006, in _gcd_import



 "<frozen importlib._bootstrap>", line 983, in _find_and_load



 "<frozen importlib._bootstrap>", line 967, in _find_and_load_unlocked



 "<frozen importlib._bootstrap>", line 677, in _load_unlocked



 "<frozen importlib._bootstrap_external>", line 728, in exec_module



 "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed



 "/usr/local/lib/python3.7/dist-packages/pip/_internal/commands/install.py", line 24, in <module>


from pip._internal.cli.req_command import RequirementCommand, with_cleanup



 "/usr/local/lib/python3.7/dist-packages/pip/_internal/cli/req_command.py", line 16, in <module>


from pip._internal.index.package_finder import PackageFinder



 "/usr/local/lib/python3.7/dist-packages/pip/_internal/index/package_finder.py", line 21, in <module>


from pip._internal.index.collector import parse_links



 "/usr/local/lib/python3.7/dist-packages/pip/_internal/index/collector.py", line 14, in <module>


from pip._vendor import html5lib, requests



 "/usr/local/lib/python3.7/dist-packages/pip/_vendor/requests/__init__.py", line 114, in <module>


from . import utils



 "/usr/local/lib/python3.7/dist-packages/pip/_vendor/requests/utils.py", line 25, in <module>


from . import certs



 "/usr/local/lib/python3.7/dist-packages/pip/_vendor/requests/certs.py", line 15, in <module>


from pip._vendor.certifi import where



 "/usr/local/lib/python3.7/dist-packages/pip/_vendor/certifi/__init__.py", line 1, in <module>


from .core import contents, where



 "/usr/local/lib/python3.7/dist-packages/pip/_vendor/certifi/core.py", line 12, in <module>


from importlib.resources import read_text



 "/usr/lib/python3.7/importlib/resources.py", line 11, in <module>


from typing import Iterable, Iterator, Optional, Set, Union
# noqa: F401



 "/usr/local/lib/python3.7/dist-packages/typing.py", line 1356, in <module>


class Callable(extra=collections_abc.Callable, metaclass=CallableMeta):



 "/usr/local/lib/python3.7/dist-packages/typing.py", line 1004, in __new__


self._abc_registry = extra._abc_registry


AttributeError: type object 'Callable' has no attribute '_abc_registry'

