/usr/share/doc/spamassassin/examples/muttrc is in spamassassin 3.4.1-8build1.
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1 2 3 4 5 6 7 | # Add this to your ~/.muttrc to integrate spamassassin and mutt
# spamassassin report and classify as spam
macro index S "|/usr/bin/spamassassin -r"
# spamassassin classify as ham
macro index H "|/usr/bin/sa-learn --ham --no-sync"
# rebuild the spamassassin bayes filter db
macro index R "!/usr/bin/sa-learn --sync"
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