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<!-- This is similar to the tweet you saw before... -->
 <p>
    <strong class="realname">Curiosity Rover</strong> ‏
    <strong class="username">@MarsCuriosity</strong>   
</p>  
<p class="maintext">
    From chemist to explorer to mayor, I am one busy bot. ...
</p>                            
<p class="date">7 Oct 12</p>                         

<!-- Now there is a div enclosing the entire tweet: -->
<div class="tweet"> <!-- The div starts on this line... -->
     <p>
        <strong class="realname">Curiosity Rover</strong> ‏
        <strong class="username">@MarsCuriosity</strong>   
    </p>  
    <p class="maintext">
        From chemist to explorer to mayor, I am one busy bot. ...
    </p>                            
    <p class="date">7 Oct 12</p>
</div> <!-- ... and the div ends on this line. -->