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 # Slack bot for ASTRON/JIVE daily image
 
 Post the ASTRON/JIVE daily image from http://www.astron.nl/dailyimage/ to
-the #daily-image channel on the Astron Slack at radio-observatory.slack.com
\ No newline at end of file
+the #daily-image channel on the Astron Slack at radio-observatory.slack.com
+
+To use, put a file called `slack_secret` in the same directory as the main
+script, and put one line with a slack secret in this file. The slack secret
+should look like
+
+```
+T3XTAT1R3/K010AZ6BD2I/alqRFnPDndremLfc92aLd4sx
+```