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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 _add_facl_rules(self):
 """ Apply ACL rules on the directory using setfacl program. Raises CommandDoesNotExistException if the command is not present on the system. :return: None """

        setfacl_command_exists()
        # we are not using pylibacl b/c it's only for python 2
        if self.facl_rules:
            logger.debug("adding ACLs %s to %s", self.facl_rules, self.path)
            r = ",".join(self.facl_rules)
            run_cmd(["setfacl", "-m", r, self.path])