Installing old/deprecated packages

[riveravaldez <riveravaldezmail@gmail.com>]

Hi,

I have this `phwmon.py`[1] which I use with fluxbox to have a couple
of system monitors at hand. It depends on some python2 packages, so
stopped working some time ago.
I've just made it work, installing manually (# apt-get install packages.deb)
this packages that I've downloaded from Debian OldStable official archives:

python-psutil
python-is-python2 (this is in fact in Testing)
python-numpy
python-pkg-resources
python-cairo
libffi6
python-gobject-2
python-gtk2

Therefore, my questions:

How safe is this?

Is it better to install them as I did, or adding the corresponding line in
sources.list and pull them from there? Is there any difference?

Thanks a lot in advance and sorry (I previously asked this in another
thread...)

Kind regards!

1] https://gitlab.com/o9000/phwmon