def push(self, exit):
        """Registers a callback with the standard __exit__ method signature

        Can suppress exceptions the same way __exit__ methods can.

        Also accepts any object with an __exit__ method (registering a call
        to the method instead of the object itself)
        """
        # We use an unbound method rather than a bound method to follow
        # the standard lookup behaviour for special methods
        _cb_type = _get_type(exit)
        try:
            exit_method = _cb_type.__exit__
        except AttributeError:
            # Not a context manager, so assume its a callable
            self._exit_callbacks.append(exit)
        else:
            self._push_cm_exit(exit, exit_method)
        return exit # Allow use as a decorator
Registers a callback with the standard __exit__ method signature

        Can suppress exceptions the same way __exit__ methods can.

        Also accepts any object with an __exit__ method (registering a call
        to the method instead of the object itself)
        
product/gradle-plugin/src/main/python/pip/_vendor/contextlib2.py