Assessment not to be invalid on certain grounds
81. No assessment, notice, summons or other proceedings,
made or issued or taken or purported to have been made or issued or
taken in pursuance of any of the provisions of this Act shall be invalid
or shall be deemed to be invalid merely by reason of any mistake,
defect or omission in such assessment, notice, summons or other
proceeding if such assessment, notice, summons or other proceeding is in
substance and effect in conformity with or according to the intent and
purpose of this Act.
 and Imposition of Tax Act, 2015){kind=link}