Traceback (most recent call last):

 "/usr/local/lib/python2.7/dist-packages/kivy/core/window/window_sdl2.py", line 525, in mainloop
self._mainloop()

 "/usr/local/lib/python2.7/dist-packages/kivy/core/window/window_sdl2.py", line 290, in _mainloop
EventLoop.idle()

 "/usr/local/lib/python2.7/dist-packages/kivy/base.py", line 327, in idle
Clock.tick()

 "/usr/local/lib/python2.7/dist-packages/kivy/clock.py", line 483, in tick
self._process_events()

 "/usr/local/lib/python2.7/dist-packages/kivy/clock.py", line 615, in _process_events
event.tick(self._last_tick, remove)

 "/usr/local/lib/python2.7/dist-packages/kivy/clock.py", line 374, in tick
ret = callback(self._dt)

 "/home/kuldeep/Downloads/kivy-designer-master/designer/nodetree.py", line 115, in _refresh
self._clear_tree(self.tree, self.tree.root)

 "/home/kuldeep/Downloads/kivy-designer-master/designer/nodetree.py", line 108, in _clear_tree
self._clear_tree(tree, n)

 "/home/kuldeep/Downloads/kivy-designer-master/designer/nodetree.py", line 108, in _clear_tree
self._clear_tree(tree, n)

 "/home/kuldeep/Downloads/kivy-designer-master/designer/nodetree.py", line 107, in _clear_tree
for n in node.nodes[:]:

 "kivy/weakproxy.pyx", line 19, in kivy.weakproxy.WeakProxy.__getattr__ (/tmp/pip-build-PcmCq7/kivy/kivy/weakproxy.c:1097)

 "kivy/weakproxy.pyx", line 15, in kivy.weakproxy.WeakProxy.**ref** (/tmp/pip-build-PcmCq7/kivy/kivy/weakproxy.c:1004)ReferenceError: weakly-referenced object no longer exists
Traceback (most recent call last):


 "/usr/bin/mailpile", line 10, in <module>

sys.exit(main())


 "/usr/lib/python2.7/dist-packages/mailpile/__main__.py", line 6, in main

Main(sys.argv[1:])


 "/usr/lib/python2.7/dist-packages/mailpile/app.py", line 247, in Main

readline.write_history_file(session.config.history_file())
AttributeError: 'NoneType' object has no attribute 'write_history_file'
