pycompat: introduce identity function as a compat stub
I was sometimes too lazy to use 'str' instead of 'lambda a: a'. Let's add
a named function for that purpose.
fixbundle() {
grep -v 'saving bundle' | grep -v 'saved backup' | \
grep -v added | grep -v adding | \
grep -v "unable to find 'e' for patching" | \
grep -v "e: No such file or directory" | \
cat
}