ORA-01045

When ever in the past I had ORA-01045 there's only 1 solution I ever used (really), which is:

grant connect, resource to xyz ;

This works, no problem. But it's assumingly not the best way of doing this.

The user is literally missing the Create Session privilege

So the question is not how to let 1 user into the database, but my question is this: I'm looking at an existing user (which obviously can log in the database), and I'm wondering : which exact command was used to setup this account. I'm not asking to go back into time, but just to try and determine how it was done, based on the current config which I'm looking at. I have full access to that database, no problem.