exc.py

# -*- coding: utf-8 -*-

import six

class FooException(Exception):
	def __init__(self, message):
		if six.PY2 and isinstance(message, six.text_type):
			super(FooException, self).__init__(message.encode("utf-8"))
		else:
			super(FooException, self).__init__(message)

	def __unicode__(self):
		return str(self).decode("utf-8")