def __init__(self, prop):
        self.prop = prop
        self.cascade = prop.cascade
        self.mapper = prop.mapper
        self.parent = prop.parent
        self.secondary = prop.secondary
        self.direction = prop.direction
        self.is_backref = prop.is_backref
        self.post_update = prop.post_update
        self.foreign_keys = prop.foreign_keys
        self.passive_deletes = prop.passive_deletes
        self.passive_updates = prop.passive_updates
        self.enable_typechecks = prop.enable_typechecks
        self.key = prop.key
        if not self.prop.synchronize_pairs:
            raise exceptions.ArgumentError("Can't build a DependencyProcessor for relation %s.  No target attributes to populate between parent and child are present" % self.prop)