What is __return__?

Question

I am debugging a script in Python 3.1 and discovered this:

(Pdb) p locals() {\'count\': 264, \'self\': , \'depth\': 1, \'offset\': 0, \'_

Answer 1

The __return__ keyword only appears in the debugger code:

matt@stanley:~/src/Python-3.2$ grep -R __return__ .
./Lib/pdb.py:        frame.f_locals['__return__'] = return_value
./Lib/pdb.py:        if '__return__' in self.curframe_locals:
./Lib/pdb.py:            self.message(repr(self.curframe_locals['__return__']))
./Lib/bdb.py:        if '__return__' in frame.f_locals:
./Lib/bdb.py:            rv = frame.f_locals['__return__']