More updates:

 * add a verbose flag, useful for debugging
 * fix the canonicalization of old-style print statement
 * fix broken py_func wrapper
 * expand the conditional statement to return a dummy value if we cannot fine any return values, and call without an assignment so that the side effect guards catch it instead
 * streamline the converter tests a bit more
 * avoid aliasing "tf" and "self" in the side effect guards
 * improve the namer to generate shorter names

PiperOrigin-RevId: 185002802