$ sudo apt-get update
$ sudo apt-get install python-transmissionrpc 

python-transmissionrpc is installed in your system.

Make ensure the python-transmissionrpc package were installed using the commands given below,

$ sudo dpkg-query -l | grep python-transmissionrpc *

You will get with python-transmissionrpc package name, version, architecture and description in a table

python-transmissionrpc package basic information: