BeautifulSoup 如何处理这种情况？

<div class="a">aaa1</div>
<div class="b">bbb1</div>

<div class="a">aaa2</div>

<div class="a">aaa3</div>
<div class="b">bbb3</div>

<div class="a">aaa4</div>

<div class="a">aaa5</div>
<div class="b">bbb5</div>

<div class="a">aaa6</div>
抓出如下输出：
aaa1
bbb1
===
aaa2
===
aaa3
bbb3
===
aaa4
===
aaa5
bbb5
===
aaa6

谢谢！