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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 remove_zone_record(self, id, domain, subdomain=None):
 """ Remove the zone record with the given ID that belongs to the given domain and sub domain. If no sub domain is given the wildcard sub-domain is assumed. """


        if subdomain is None:
            subdomain = "@"

        _validate_int("id", id)

        self._call("removeZoneRecord", domain, subdomain, id)