I am new to cassandra ! Have downloaded the apacahe cassandra 2.1.2 package and initialy was able to connect to cqlsh but then after installing CCM i am unable to connect ,
You could export PYTHONPATH, to include site package folder where cqlshlib exists
First find the path where cqlshlib exists
find /usr/lib/ -name cqlshlib
Export the path using below variable name
export PYTHONPATH=/usr/lib/python2.7/site-packages/