IPA is just a zip file containing the Payload folder, which in turn contains a set of applications. As such, there is no code in IPA - just a compiled executable. You can unzip it and look in the Payload folder, but all you see is the executable code. You could parse the code (do not ask me how - I never tried this), but if you need to do this, I wonder why you do not have access to the source in the first place ...
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