When you update or install something in openmediavault 4.x and saw theses
Exception ignored in: <function WeakValueDictionary.__init__.<locals>.remove at 0x7fb7d2d82730> Traceback (most recent call last): File "/usr/lib/python3.5/weakref.py", line 117, in remove TypeError: 'NoneType' object is not callable Exception ignored in: <function WeakValueDictionary.__init__.<locals>.remove at 0x7fb7d2d82730> Traceback (most recent call last): File "/usr/lib/python3.5/weakref.py", line 117, in remove TypeError: 'NoneType' object is not callable
You can workaround it with
curl -L https://raw.githubusercontent.com/python/cpython/3.5/Lib/weakref.py > /usr/lib/python3.5/weakref.py