dephell dep --help throws traceback

[mimi1vx]

Short description

simple call dephell dep --help throw traceback

Output

simple warning about nonexistent command

Steps to reproduce

$ dephell dep --help
...

Traceback

Traceback (most recent call last):
  File "/usr/bin/dephell", line 11, in <module>
    load_entry_point('dephell==0.8.3', 'console_scripts', 'dephell')()
  File "/usr/lib/python3.8/site-packages/dephell/cli.py", line 84, in entrypoint
    exit(main(argv[1:]))
  File "/usr/lib/python3.8/site-packages/dephell/cli.py", line 44, in main
    parser._print_message(parser.format_help(command=command))
  File "/usr/lib/python3.8/site-packages/dephell_argparse/_parser.py", line 163, in format_help
    self._format_commands(formatter=formatter, command=command)
  File "/usr/lib/python3.8/site-packages/dephell_argparse/_parser.py", line 183, in _format_commands
    elif command.guesses:
  File "/usr/lib/python3.8/site-packages/dephell_argparse/_cached_property.py", line 18, in __get__
    value = obj.__dict__[self.func.__name__] = self.func(obj)
  File "/usr/lib/python3.8/site-packages/dephell_argparse/_command.py", line 85, in guesses
    for name in self.argv[:2]:
  File "/usr/lib/python3.8/site-packages/dephell_argparse/_command.py", line 29, in argv
    return self._argv[self.words:]
  File "/usr/lib/python3.8/site-packages/dephell_argparse/_cached_property.py", line 18, in __get__
    value = obj.__dict__[self.func.__name__] = self.func(obj)
  File "/usr/lib/python3.8/site-packages/dephell_argparse/_command.py", line 25, in words
    return len(self.match.split())
AttributeError: 'NoneType' object has no attribute 'split'

...

Config

[tool.dephell.main]
...

Versions

...

[orsinium]

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