Python file/line when the current C execution frame is inside
PyEval_EvalFrame. These are commented out by default because GDB sometimes
crashes as a result (seems like a GDB bug).
Add a pyframe command that displays the current Python stack frame. If the
marked lines are uncommented, it will also cause Emacs/XEmacs to display the
current file/line.
work with core dumps because it avoids calling any Python API routines. The
latter prints all the local variable values as well as the stack frames but
won't work with core dumps because it relies on _PyObject_Dump to print
variables.
