擅长:python、mysql、java
<pre><code>import pandas as pd
df1 = pd.read_csv('1.csv')
df2 = pd.read_csv('2.csv')
out = pd.merge(df1, df2, on='customer_Email', how='left')
out.loc[~out['customer_Email'].isin(df2.drop_duplicates(subset='customer_Email', keep=False)['customer_Email'].tolist()), 'Fraud'] = None
out
</code></pre>
<p><strong>给出:</strong></p>
<pre><code> customer_Email Fraud ID
0 name_0 0.0 0
1 name_1 NaN 1
2 name_1 NaN 5
3 name_2 1.0 2
4 name_3 1.0 3
5 name_4 0.0 4
6 name_1 NaN 1
7 name_1 NaN 5
</code></pre>