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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 set(self, key, value):
 """Sets the rules config for a given key. Args: key (str):
 rules config key to set value (str):
 value to set for the rules config key See: https://auth0.com/docs/api/management/v2#!/Rules_Configs/put_rules_configs_by_key """

        url = self._url('{}'.format(key))
        body = {'value': value}
        return self.client.put(url, data=body)