xxxxx.xxxxx.adgroup.catmatch.get
        ===================================
        取得一个推广组的类目出价

def get(self, adgroup_id, nick=None):
        '''xxxxx.xxxxx.adgroup.catmatch.get
        ===================================
        取得一个推广组的类目出价'''
        request = TOPRequest('xxxxx.xxxxx.adgroup.catmatch.get')
        request['adgroup_id'] = adgroup_id
        if nick!=None: request['nick'] = nick
        self.create(self.execute(request), fields=['success','result','success','result_code','result_message'], models={'result':ADGroupCatmatch})
        return self.result