I have been using your library a bit today and was trying to convert dictionaries with spaces in the keys. This didn't work so well :-) I made a change to your code to replace any spaces in keys with underscores. Maybe you'd like to include this?
Substitute spaces for underscore in dictionary keys with spaces
v 1.3.3 fixed issue #12 on github
Thank you for raising this issue and suggesting a fix. I have implemented your suggestion - replacing spaces with underscores in element names - as of version 1.3.3.