def __call__(self, argument_parser, always_complete_options=True, exit_method=os._exit, output_stream=None,<EOL>exclude=None, validator=None):
self.__init__(argument_parser, always_complete_options, exclude)<EOL>if '<STR_LIT>' not in os.environ:<EOL><INDENT>return<EOL><DEDENT>global debug_stream<EOL>try:<EOL><INDENT>debug_stream = os.fdopen(<NUM_LIT:9>, '<STR_LIT:w>')<EOL><DEDENT>except:<EOL><INDENT>debug_stream = sys.stderr<EOL><DEDENT>if output_stream is None:<EOL><INDENT>try:<EOL><INDENT>output_stream = os.fdopen(<NUM_LIT:8>, '<STR_LIT:wb>')<EOL><DEDENT>except:<EOL><INDENT>debug("<STR_LIT>")<EOL>exit_method(<NUM_LIT:1>)<EOL><DEDENT><DEDENT>if validator is None:<EOL><INDENT>validator = default_validator<EOL><DEDENT>self.validator = validator<EOL>ifs = os.environ.get('<STR_LIT>', '<STR_LIT>')<EOL>if len(ifs) != <NUM_LIT:1>:<EOL><INDENT>debug("<STR_LIT>".format(v=ifs))<EOL>exit_method(<NUM_LIT:1>)<EOL><DEDENT>comp_line = os.environ['<STR_LIT>']<EOL>comp_point = int(os.environ['<STR_LIT>'])<EOL>if USING_PYTHON2:<EOL><INDENT>comp_point = len(comp_line[:comp_point].decode(sys_encoding))<EOL><DEDENT>else:<EOL><INDENT>comp_point = len(comp_line.encode(sys_encoding)[:comp_point].decode(sys_encoding))<EOL><DEDENT>if USING_PYTHON2:<EOL><INDENT>comp_line = comp_line.decode(sys_encoding)<EOL><DEDENT>cword_prequote, cword_prefix, cword_suffix, comp_words, first_colon_pos = split_line(comp_line, comp_point)<EOL>if os.environ['<STR_LIT>'] == "<STR_LIT:2>":<EOL><INDENT>comp_words.pop(<NUM_LIT:0>)<EOL><DEDENT>debug("<STR_LIT>".format(l=comp_line, pq=cword_prequote, p=cword_prefix),<EOL>"<STR_LIT>".format(s=cword_suffix),<EOL>"<STR_LIT>", comp_words)<EOL>completions = self._get_completions(comp_words, cword_prefix, cword_prequote, first_colon_pos)<EOL>debug("<STR_LIT>", completions)<EOL>output_stream.write(ifs.join(completions).encode(sys_encoding))<EOL>output_stream.flush()<EOL>debug_stream.flush()<EOL>exit_method(<NUM_LIT:0>)<EOL>
:param argument_parser: The argument parser to autocomplete on
:type argument_parser: :class:`argparse.ArgumentParser`
:param always_complete_options: Whether or not to autocomplete options even if an option string opening character (normally ``-``) has not been entered
:type always_complete_options: boolean
:param exit_method: Method used to stop the program after printing completions. Defaults to :meth:`os._exit`. If you want to perform a normal exit that calls exit handlers, use :meth:`sys.exit`.
:type exit_method: callable
:param exclude: List of strings representing options to be omitted from autocompletion
:type exclude: iterable
:param validator: Function to filter all completions through before returning (called with two string arguments, completion and prefix; return value is evaluated as a boolean)
:type validator: callable

.. note:: If you are not subclassing CompletionFinder to override its behaviors, use ``argcomplete.autocomplete()`` directly. It has the same signature as this method.

Produces tab completions for ``argument_parser``. See module docs for more info.

Argcomplete only executes actions if their class is known not to have side effects. Custom action classes can be
added to argcomplete.safe_actions, if their values are wanted in the ``parsed_args`` completer argument, or their
execution is otherwise desirable.