pandas - How to fill the column based on a few conditions from other columns

Question

I have two columns with letters.

<table>
<thead>
<tr>
<th>First_col</th>
<th>Second_col</th>
</tr>
</thead>
<tr>
<td>A</td>
<td>A</td>
</tr>
<tr>
<td>B</td>
<td>A</td>
</tr>
<tr>
<td>A</td>
<td>B</td>
</tr>
</table>

question from:https://stackoverflow.com/questions/65860420/how-to-fill-the-column-based-on-a-few-conditions-from-other-columns

Answer 1

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