Add or replace the JSON policy associated with the bucket.

        :type policy: str
        :param policy: The JSON policy as a string.

def set_policy(self, policy, headers=None):
        """
        Add or replace the JSON policy associated with the bucket.

        :type policy: str
        :param policy: The JSON policy as a string.
        """
        response = self.connection.make_request('PUT', self.name,
                                                data=policy,
                                                query_args='policy',
                                                headers=headers)
        body = response.read()
        if response.status >= 200 and response.status <= 204:
            return True
        else:
            raise self.connection.provider.storage_response_error(
                response.status, response.reason, body)