Formatting a single row as CSV
The csv module wraps the _csv module, which is written in C.  You could grab the source for it and modify it to not require the file-like object, but poking around in the module, I don't see any clear way to do it without recompiling.
I'm creating a script to convert a whole lot of data into CSV format. It runs on Google AppEngine using the mapreduce API, which is only relevant in that it means each row of data is formatted and output separately, in a callback function.
I want to take advantage of the logic that already exists in the csv module to convert my data into the correct format, but because the CSV writer expects a file-like object, I'm having to instantiate a StringIO for each row, write the row to the object, then return the content of the object, each time.
This seems silly, and I'm wondering if there is any way to access the internal CSV formatting logic of the csv module without the writing part.