Better handle missing error.message

from werkzeug.exceptions import default_exceptions

from werkzeug.exceptions import HTTPException

from pprint import pprint

class JSONExceptionHandler(object):

    def __init__(self, app=None):

            self.init_app(app)

    def std_handler(self, error):

        message = error.description if isinstance(error, HTTPException) else error.message

        if isinstance(error, HTTPException):

            message = error.description

        elif hasattr(error, 'message'):

            message = error.message

        else:

            message = str(error)

        status_code = error.code if isinstance(error, HTTPException) else 500

        response = {