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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 quotes_by_instrument_urls(cls, client, urls):
 """ fetch and return results """

        instruments = ",".join(urls)
        params = {"instruments": instruments}
        url = "https://api.robinhood.com/marketdata/quotes/"
        data = client.get(url, params=params)
        results = data["results"]
        while "next" in data and data["next"]:
            data = client.get(data["next"])
            results.extend(data["results"])
        return results