Figuring out why function implementations aren't available

[Thomas Levine <_ thomaslevine com>]

A plugin I am writing is behaving strangely, and I am
having trouble figuring out why I'm seeing no error messages.

The spellbook contains plugin.xml (attached) and sheetmusic.py
(below).

    import libsheetmusic.main
    sheetmusic_functions = libsheetmusic.main.functions()

When I put the spellbook in the appropriate place, set PYTHONPATH
to the directory containing libsheetmusic, open Gnumeric, and run
a function from the spellbook,

    =diatonic_scale('D3'))

the cell renders this,

    Function implementation not available.

and I see no error messages. When I switch sheetmusic.py to
the file below,

    import libsheetmusic.main # in case this is creating an error
    sheetmusic_functions = {'diatonic_scale': lambda _: 3}

it works as you'd expect.

Any ideas?

Thanks

Tom

Attachment: sheetmusic.py
Description: Text Data