class ToTo(EntityType):

    permissions = {

        'read': ('managers',),

        'add': ('managers',),

        'update': ('managers',),

        'delete': ('managers',),

        }

    attr = String()

class attr(RelationType):

    permissions = {

        'read': ('managers', ),

        'add': ('managers', RRQLExpression('S bla Y'),),

        'delete': ('managers',),

        }