title: How to appende Datetime to a DataFrame when exporting
body: <p>I have a DataFrame that needs to be exported, however I don't know how to append the Datetime properly. This has to be exported every month.</p>
  <p>some of the arguments I used:</p>
  <pre><code>df_export = df.to_csv(path/export.txt, sep=';',index=False,line_terminator=&quot;\r\n&quot;)
  </code></pre>
  <p>The file should be something like this:</p>
  <pre><code>export_aaaa_mm.txt
  </code></pre>