If bss is installed in /usr/local/lib/python2.7, then bss_prepare_data_for_tbm.py should go in the bin directory where you are calling python from. For e.g.
/usr/local/bin, /usr/bin etc..
you can do
which pip
or
which python
bss_prepare_data_for_tbm.py should be in the bin directory where your pip or python is located.
S