擅长:python、mysql、java
<p>如果我的理解是正确的,您可以使用<code>mode</code></p>
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<p>数据输入</p>
<pre><code>df=pd.DataFrame({'Medicine_ID':["A","B","C","D"],'Counterfeit_Weight':[999,2,np.nan,np.nan]})
df1=pd.DataFrame({'Medicine_ID':["A","A","B","B","C","C","C","D","D","D"],'Counterfeit_Weight':[2,np.nan,2,np.nan,2,2,np.nan,1,1,2]})
</code></pre>
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<p>解决方案</p>
^{pr2}$