'Will return a :class:`OverrideFieldData` which wraps the field data
given in `wrapped` for the given `user`, if override providers are
configred.  If no override providers are configured, using the Django
setting, `FIELD_OVERRIDE_PROVIDERS`, returns `wrapped`, eliminating
any performance impact of this feature if no override providers are
configured.'

@classmethod
def wrap(cls, user, course, wrapped):

    if (cls.provider_classes is None):
        cls.provider_classes = tuple((resolve_dotted(name) for name in settings.FIELD_OVERRIDE_PROVIDERS))
    enabled_providers = cls._providers_for_course(course)
    if enabled_providers:
        return cls(user, wrapped, enabled_providers)
    return wrapped
