def _activity_or_list(value):
        """Tries to convert value to :class:`tincan.ActivityList`

        :setter type: :class:`tincan.ActivityList`
        :rtype: :class:`tincan.ActivityList`
        """
        result = value
        if value is not None and not isinstance(value, ActivityList):
            try:
                result = ActivityList([Activity(value)])
            except (TypeError, AttributeError):
                result = ActivityList(value)
        return result