I have a ... file ... in the form of ...

Remember that whitespace is but the callow plaything of the HTML/XML renderer of the browser with which you, I and others view your post. Do you see form or structure in the data as posted? It's possible to guess at this structure, but why should we? Please update your original post to use  <c> ... </c> or  <code> ... </code> tags around input (and output, if such there be) data as well as your code. Please see Markup in the Monastery and Writeup Formatting Tips.

I have some code and know what it's doing ...

The title of your post implies that the code works, but the posted code does not compile. It's possible by fiddling around with it a bit to make it compile, but then, as noted above, it doesn't really do anything. Again, why should we guess about all this? Please give a small, executable code example that operates on a small, downloadable data sample and that illustrates to us what it is that you know it's doing. (And a verbal description of what it's supposed to do would be helpful, too.) Please see I know what I mean. Why don't you?.