def METHOD_NAME(self, params=None):
    if params is None:
        params = {}
    Resource.verify_keys(params, Subscription.create_signature())
    response = self.config.http().post(self.config.base_merchant_path() + "/subscriptions", {"subscription": params})
    if "subscription" in response:
        return SuccessfulResult({"subscription": Subscription(self.gateway, response["subscription"])})
    elif "api_error_response" in response:
        return ErrorResult(self.gateway, response["api_error_response"])