擅长:python、mysql、java
<pre><code>import datetime
#Only use the following line if the column type for your 'date' column is
# string
df['date'] = pd.to_datetime(df['date'])
(max(df['date']) - pd.tseries.offsets.BDay(260)).strftime('%Y-%m-%d')
#The line above produces:
# '2015-01-06'
</code></pre>