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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 shorten(self, url, custom=None, give_delete=True):
 """ Sends a URL shorten request to the API. :param url: the URL to shrink :type url: str :param custom: a custom URL to request :type custom: str :param give_delete: would we like a deletion key to be returned? :type give_delete: bool :return: the API response JSON dict :rtype: dict """

        data = self.fetch("/submit", {
            "long": url,
            "short": custom if custom else "",
            "delete": "true" if give_delete else ""
        })

        return data