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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_cmd_help(self):
 """ Get the single-line help of this command. :returns: ``self.help``, if defined :returns: The first line of the docstring, without the trailing dot, if present. :returns: None, otherwise """

        try:
            return self.help
        except AttributeError:
            pass
        try:
            return get_localized_docstring(
                self, self.get_gettext_domain()
            ).splitlines()[0].rstrip('.').lower()
        except (AttributeError, IndexError, ValueError):
            pass