Hey Lysandros.

Take a look at https://github.com/python/cpython/blob/master/Lib/wave.py#L126-L139

Notice how there's a Chunk made from the `file` argument but then another Chunk created using the previous chunk as a file.

While it might seem like self.size_read is magically changing between the steps, the thing to realize there is that self.file is another chunk and when you step, you're stepping into the seek of another Chunk instance, which has its own self.size_read