***** createPaymentRequestXML *****:
<xml><appid><![CDATA[appid]]></appid><mch_id>mch_id</mch_id><nonce_str><![CDATA[ywt7jrq2du4n1270356vl1400dht5ecm]]></nonce_str><out_trade_no>000000029</out_trade_no><sign_type><![CDATA[MD5]]></sign_type><sign><![CDATA[87334C529842B1D4660F1E27A4F02FE9]]></sign></xml>
***** responseXml *****:
<xml>
<return_code><![CDATA[SUCCESS]]></return_code>
<return_msg><![CDATA[OK]]></return_msg>
<appid><![CDATA[appid]]></appid>
<mch_id><![CDATA[mch_id]]></mch_id>
<sub_mch_id><![CDATA[]]></sub_mch_id>
<nonce_str><![CDATA[MUz36sdZ7hYkOrf4]]></nonce_str>
<sign><![CDATA[B996A537AD116B34FB8008E71274FED8]]></sign>

<result_code><![CDATA[SUCCESS]]></result_code>
</xml>