def remove(self, elem):
        """Remove a requirement.

        :param elem: a string or :class:`Requirement` instance.
        """
        if isinstance(elem, text_type):
            for requirement in self:
                if requirement.package == elem:
                    return super(Requirements, self).remove(requirement)
        return super(Requirements, self).remove(elem)
def _prepare_filename(
        self, action_name: Optional[str] = None, extension: str = ".txt", split_token: str = "-"
    ) -> str:
        args = []
        if self._stage is not None:
            args.append(self._stage)
        if self.filename:
            args.append(self.filename)
        if self._local_rank is not None:
            args.append(str(self._local_rank))
        if action_name is not None:
            args.append(action_name)
        filename = split_token.join(args) + extension
        return filename