如何在下面的html代码中提取“已发货:(SJ顺丰 051131145456)”中的单号“051131145456”，单号位数会变，注意：单号前面有一个空格。正则表达式应该怎么样写
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物流信息
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<table style="border: 1px solid #ECECEC; height: 125px; padding-left: 5px; padding-right: 5px; background-color: #EEF7FF; width: 100%">
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<img style="margin-top: 8px;" src="../Resources/Images/Box/qrcode_for_gh.png" /></td>
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<td style="font-size: 14px; vertical-align: top;">您可以随时接收物流动态、为包裹付款、获取最新的活动信息。</td>
<td style="font-size: 14px; width: 260px; vertical-align: top;"><span style="font-size: 14px; float: right;">以最方便的方式玩转海淘＞</span><br />
<span style="font-size: 14px; float: right;">扫一扫，关注微信公众号「」</span></td>
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<input type="hidden" id="boxcount" value="1" />
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<label for="tab1"><a style="cursor: pointer;">XJ202002232539531</a></label>
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<div class="result-top"><span class="col1">时间</span><span class="col2">地点和跟踪进度</span></div>
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<td class="row1">2020/3/8 10:12:11</td>
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<td>已发货:(SJ顺丰 051131145456) <a target = "_blank" href="http://www.kuaidi100.com/chaxun?com=shunfeng&nu=051131145456" style="text-decoration:none;" onclick="AddQuery()">国内物流查询>></a></td>
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<td class="row1">2020/3/8 10:11:11</td>
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<td>已清关 </td>
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<td class="row1">2020/3/5 13:58:00</td>
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<td>已到达清关口岸 </td>
