This code errors on *this* and *that*, is it really written in them?
Python 2 / Python 3, 60 bytes



print("This program errors out in Python %d :P"%(3/2*2))*1;a



Python 2 got NameError: name 'a' is not defined
Python 3 got unsupported operand type(s) for *: 'NoneType' and 'int'


Python 2:


/ is integer division, 3 / 2 got 1; int(3 / 2 * 2) is 2.
print is a statement, so the first statement read as print((...)*1), here *1 means repeating the string once.
second statement referenced a non-existing variable, which caused the error.
Try it online!


Python 3: 


'/' is floating number division, 3 / 2 got 1.5; int(3 / 2 * 2) is 3.
print is a function, so the first statement read as (print(...))*1.
function print returns None; Multiplication do not work on None x int, so it report "unsupported operand".
Try it online!