/usr/bin/mailnag-config is in mailnag 1.0.0-1.
This file is owned by root:root, with mode 0o755.
The actual contents of the file can be viewed below.
1 2 3 4 5 | #!/bin/bash
LIB_DIR=/usr/lib/python2.7/dist-packages/Mailnag
cd $(dirname $(readlink -f $0))
python2 $LIB_DIR/config.py $@
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