<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def unset(self, key):
 """Removes the rules config for a given key. Args: key (str):
 rules config key to remove See: https://auth0.com/docs/api/management/v2#!/Rules_Configs/delete_rules_configs_by_key """

        params = {
            'key': key
        }
        return self.client.delete(self._url(), params=params)