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+Demonstration script for Debian bug #786609 http://bugs.debian.org/786609
+
+The script sets up three directories:
+
+ - aptroot: a root directory structure with /etc/apt, /var/lib/dpkg and
+   /var/cache/apt to try out apt behaviour independent of the host system
+ - exprepo: a repository with codename experimental and pin priority 500
+ - sidrepo: a repository with codename unstable and pin priority 900
+
+Then three calls to apt-get are done:
+
+ - installing pkg-a normally
+ - installing it with -t experimental
+ - installing it with aspcud as resolver
+
+See the Debian bug for more details.