I posted a quine some weeks ago here on this forum, believing there couldn't be a shorter one.

It seems like I was wrong Just figured out an even shorter one!!

only 18 characters long! (including the space)

make a file called:
print('exec __file__[:-3]').py
and copypaste this code into it:
exec __file__[:-3]

run it with your interpreter(python 2), and it will print out its source code