TypeError exception when calling service operation with a default attribute for parameter of type dateTime  #395

class DateTime(BuiltinType, AnySimpleType):
    _default_qname = xsd_ns('dateTime')
    accepted_types = (datetime.datetime,) + six.string_types

    @check_no_collection
    def xmlvalue(self, value):

        if isinstance(value, str):
            return value

        # Bit of a hack, since datetime is a subclass of date we can't just
        # test it with an isinstance(). And actually, we should not really
        # care about the type, as long as it has the required attributes
        if not all(hasattr(value, attr) for attr in ('hour', 'minute', 'second')):
            value = datetime.datetime.combine(value, datetime.time(
                getattr(value, 'hour', 0),
                getattr(value, 'minute', 0),
                getattr(value, 'second', 0)))

        if getattr(value, 'microsecond', 0):
            return isodate.isostrf.strftime(value, '%Y-%m-%dT%H:%M:%S.%f%Z')
        return isodate.isostrf.strftime(value, '%Y-%m-%dT%H:%M:%S%Z')