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<html><head><style>table, th, td { border: 1px solid black;}tr.collapse { visibility: collapse;}</style></head><body><table> <tr> <th>Firstname</th> <th>Lastname</th> </tr> <tr> <td>Peter</td> <td>Griffin</td> </tr> <tr class="collapse"> <td>Lois</td> <td>Griffin</td> </tr></table></body></html>