Well, if the data is description of your mind then the code should produce a string that begins with description of your mind, somehow. Pulling the universe out will require examining the code's internals.

If you do S.I. in a fuzzy manner there can be all sorts of self-misconceptions; it can be easier (shorter coding) to extract an incredibly important mind, therefore you obtain not solipsism but narcissism. The prior for self importance may then be quite huge.

If you drop requirement that output string begins with description of the mind and search for the data anywhere within the output string, then a simple counter will suffice as valid code.