sectoral classification of stocks

I want to classify stocks based on the sectors/industries they are operating in. For example, one of the classification can be PSU banks which shall include Canbk, denabank, sbin, sbbj, iob, sbt and so on.

Now I have found a tedious approach to look each companies' related companies in google finance and moneycontrol and do the process manually. Can somebody let me know if this kind of sectoral classification is already available?

sectoral classification of stocks