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<p>我有以下数据，我希望将所有以SAR开头的值都放入“价格”列中。“SAR”值分散在整个数据帧中</p>
<pre><code>name,rating,random,price
"Microwave Oven Sharp 20 Litres, White, R-20AS-W",5.0 out of 5 stars,3,SAR 199.00
"REBUNE ELECTRIC OVEN 10L, RE1016",SAR 149.00 ,,
Geepas 20 Liter Microwave Oven - GMO1894,SAR 186.00 ,,
Nikai Microwave - 20 LTR -NMO515N8N,5.0 out of 5 stars,3,SAR 192.15
LG 42 Liter Neo Chef Inverter Microwave with Grill - MH8265CIS,"SAR 1,050.00 ",,
</code></pre>
<p>我想要下面这样的。如果数据不可用，则应写“不可用”：</p>
<pre><code>name,rating,random,price
"Microwave Oven Sharp 20 Litres, White, R-20AS-W",5.0 out of 5 stars,3,SAR 199.00
"REBUNE ELECTRIC OVEN 10L, RE1016",Unavailable,Unavailable,SAR 149.00
Geepas 20 Liter Microwave Oven - GMO1894,Unavailable,Unavailable,SAR 186.00
Nikai Microwave - 20 LTR -NMO515N8N,5.0 out of 5 stars,3,SAR 192.15
LG 42 Liter Neo Chef Inverter Microwave with Grill - MH8265CIS,Unavailable,Unavailable,"SAR 1,050.00 "
</code></pre>
