Attendance is of utmost importance at Pune University and you should have a minimum attendance of 75%. It is obvious that no one maintains a full record, especially in engineering. If you have at least 50% attendance, you will be fine and no one will bother you.
However, you will be told to improve your attendance if it's between 30-50%, and if it's below 30%, then the university will involve your parents and resolve the issue. you can guess, and your parents might have to be involved.
It is important to at least attend some of the lectures as your lab practicals will be evaluated and your absence can cause problems.