This is consistent with the other 'micro' modules and allows implementing
additional features in Python via e.g. micropython-lib's sys.
Note this is a breaking change (not backwards compatible) for ports which
do not enable weak links, as "import sys" must now be replaced with
"import usys".
The string "Q+?" is special in that it hashes to zero with the djb2
algorithm (among other strings), and a zero hash should be incremented to a
hash of 1.