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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 retrieve(payment_id):
 """ Retrieve a payment from its id. :param payment_id: The payment id :type payment_id: string :return: The payment resource :rtype: resources.Payment """

        http_client = HttpClient()
        response, __ = http_client.get(routes.url(routes.PAYMENT_RESOURCE, resource_id=payment_id))
        return resources.Payment(**response)