我有一个代码，当我运行它时，它返回null，条件里面的时候（）返回null
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<p style="font-family: Arial; text-align: center;" class="MsoNormal"><b><span style="font-size: 18pt;">NEW SPECIFICATIONS AND UPDATES</span></b></p>
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<span style="font-size: 11pt; font-family: Arial;"><big>Please be advise the December 2015 update for Traffic Control (TC) Signs has been released.</big><br>
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