80[Penalty for failure to furnish return of income.
271F. If a person who is
required to furnish a return of his income, as required under sub-section (1)
of section 139 or by the provisos to that
sub-section, fails to furnish such return before the end of the relevant
assessment year, the Assessing Officer may direct that such person shall pay,
by way of penalty, a sum of five thousand rupees.]