`traitlets.traitlets:link`

Signature

class link(source: t.Any, target: t.Any, transform: t.Iterable[FuncT] | None = None) → None

Link traits from different objects together so they remain in sync.

source : (object / attribute name) pair
target : (object / attribute name) pair
transform: iterable with two callables (optional): Data transformation between source and target and target and source.

class X(HasTraits):
    value = Int()

src = X(value=1)
tgt = X(value=42)
c = link((src, "value"), (tgt, "value"))

Setting source updates target objects:

src.value = 5
tgt.value