This method is like set except that it accepts customizer which is
invoked to produce the objects of path. If customizer returns undefined
path creation is handled by the method instead. The customizer is invoked
with three arguments: (nsValue, key, nsObject).
This method is like
setexcept that it acceptscustomizerwhich is invoked to produce the objects ofpath. Ifcustomizerreturnsundefinedpath creation is handled by the method instead. Thecustomizeris invoked with three arguments: (nsValue, key, nsObject).Note: This method mutates
object.