DEBUG Method Development . LOG.0.2

method to downgrade debian from a unstable tree to stable tree

step 1
put the following content in /etc/apt/preferences.d/default
Package: *
Pin: release a=stable
Pin-Priority: 1001

step 2
make your sources.list to stable pointers.
step 3
apt-get update
apt-get upgrade
next do sensibly

To Fix Things, work on a stable system and chroot to the broken system
The command “ar” can be used to extract files from debian binary package
export PYTHONPATH=/usr/lib/python2.7 for debian related for showing python module path related.

the above content may not be accurate.