how can I rewrite a(n instance) variable to a symbol?

E.g.

[IN]

something: aSomething

�� �� something := aSomething

[OUT]

something: aSomething

�� �� self write: aSomething into: #something

I can capute the input just fine... ``@var := ``@arg

but I have no idea how to convert the var into a symbol (or string).

Thanks,

Peter