'Return a tuple of ``(local_attr, remote_attr)``.
This attribute is convenient when specifying a join
using :meth:`.Query.join` across two relationships::
sess.query(Parent).join(*Parent.proxied.attr)
.. versionadded:: 0.7.3
See also:
:attr:`.AssociationProxy.local_attr`
:attr:`.AssociationProxy.remote_attr`'

@property
def attr(self):

    return (self.local_attr, self.remote_attr)
