Traceback (most recent call last):


 "/usr/lib/python3.7/socketserver.py", line 650, in process_request_thread

self.finish_request(request, client_address)


 "/usr/lib/python3.7/socketserver.py", line 360, in finish_request

self.RequestHandlerClass(request, client_address, self)


 "test5.py", line 10, in __init__

x.hide()


 "/media/james/Development/Programming/Python/beer_engine/remi/venv/lib/python3.7/site-packages/remi/gui.py", line 2474, in hide

self._base_app_instance.set_root_widget(self._old_root_widget)


 "/media/james/Development/Programming/Python/beer_engine/remi/venv/lib/python3.7/site-packages/remi/server.py", line 462, in set_root_widget

self.page.children['body'].append(widget, 'root')


 "/media/james/Development/Programming/Python/beer_engine/remi/venv/lib/python3.7/site-packages/remi/gui.py", line 1305, in append

raise ValueError('value should be a Widget (otherwise use add_child(key,other)')
ValueError: value should be a Widget (otherwise use add_child(key,other)

Traceback (most recent call last):


 "/sbin/beet", line 11, in <module>

load_entry_point('beets==1.4.9', 'console_scripts', 'beet')()


 "/usr/lib/python3.8/site-packages/beets/ui/__init__.py", line 1266, in main

_raw_main(args)


 "/usr/lib/python3.8/site-packages/beets/ui/__init__.py", line 1249, in _raw_main

subcommands, plugins, lib = _setup(options, lib)


 "/usr/lib/python3.8/site-packages/beets/ui/__init__.py", line 1144, in _setup

lib = _open_library(config)


 "/usr/lib/python3.8/site-packages/beets/ui/__init__.py", line 1201, in _open_library

get_path_formats(),


 "/usr/lib/python3.8/site-packages/beets/ui/__init__.py", line 619, in get_path_formats

path_formats.append((query, template(view.as_str())))


 "/usr/lib/python3.8/site-packages/beets/util/functemplate.py", line 571, in template

return Template(fmt)


 "/usr/lib/python3.8/site-packages/beets/util/functemplate.py", line 581, in __init__

self.compiled = self.translate()


 "/usr/lib/python3.8/site-packages/beets/util/functemplate.py", line 614, in translate

func = compile_func(


 "/usr/lib/python3.8/site-packages/beets/util/functemplate.py", line 155, in compile_func

prog = compile(mod, '<generated>', 'exec')
ValueError: Name node can't be used with 'None' constant
