Any more back-talk and you'll get a stiff sentnce.

    (If you had snipped sixteen instead of seventeen lines,
this would make more sense.)

Its not just the commas. Any non-trivial CSV implementation must be able
to deal with quoted strings which may, of course, contain quotes as well
as field separators. CSV files are both more complex and less
standardized than many people realize.

Even as a programming course exercise I'd mark down a solution that
didn't deal correctly with those factors.

And that's ignoring the bells and whistles that any proper CSV
implementation should handle, such as the ability to change the field
separator and to control the level of field quoting (quote all fields;
quote only those containing quote marks or separators; suppression of
all quoting). There's also the issue of stripping leading and trailing
spaces. Virtually all database loaders deal with CSV and all the ones
I've met have the ability to redefine the field separator.