S. 271AAA: Penalty-Search initiated on or after 1st June, 2007-Undisclosed income-Tax and interest paid-All conditions satisfied-Not mandatory-Discretion means sound discretion guided by law-Conditions under section 271AAA (2) satisfied-No penalty is attracted. [S. 132, 143(3), 271AA(1) 271AA(2), Art. 136]