def delete(self):
        # type: (_BaseResumeManager) -> None
        """Delete the resume file db
        :param _BaseResumeManager self: this
        """
        self.close()
        if self._resume_file.exists():  # noqa
            try:
                self._resume_file.unlink()
            except OSError as e:
                logger.warning('could not unlink resume db: {}'.format(e))
        for ext in ('.bak', '.dat', '.dir'):  # noqa
            fp = pathlib.Path(str(self._resume_file) + ext)
            if fp.exists():
                try:
                    fp.unlink()
                except OSError as e:
                    logger.warning('could not unlink resume db: {}'.format(e))
Delete the resume file db
        :param _BaseResumeManager self: this