Utility method to handle calls to ECS and parsing of responses.

def get_response(self, action, params, page=0, itemSet=None):
        """
        Utility method to handle calls to ECS and parsing of responses.
        """
        params['Service'] = "AWSECommerceService"
        params['Operation'] = action
        if page:
            params['ItemPage'] = page
        response = self.make_request(None, params, "/onca/xml")
        body = response.read()
        boto.log.debug(body)

        if response.status != 200:
            boto.log.error('%s %s' % (response.status, response.reason))
            boto.log.error('%s' % body)
            raise self.ResponseError(response.status, response.reason, body)

        if itemSet == None:
            rs = ItemSet(self, action, params, page)
        else:
            rs = itemSet
        h = handler.XmlHandler(rs, self)
        xml.sax.parseString(body, h)
        return rs