Copy object variable

How do I...?
1

Hi all
Any idea how to copy a variable value from one instance to another instance of the same object
for example
Instance one has variables : id=1 ,life=50
instance two has variables : id=2 , life=90

I want to copy 50 to 90
Thanks

2

Since they are instances of the same object, you should copy 90 to a temporary scene variable then copy it to the other instance.