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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 upcoming_releases(self, product):
 """ Get upcoming releases for this product. Specifically we search for releases with a GA date greater-than or equal to today's date. :param product: str, eg. "ceph" :returns: deferred that when fired returns a list of Munch (dict-like) objects representing all releases, sorted by shortname. """

        url = 'api/v6/releases/'
        url = url + '?product__shortname=' + product
        url = url + '&ga_date__gte=' + date.today().strftime('%Y-%m-%d')
        url = url + '&ordering=shortname_sort'
        releases = yield self._get(url)
        result = munchify(releases)
        defer.returnValue(result)