title: How to use pyftsubset of Fonttools inside of the python environment, not from the command line
body: <p>I need to subset very many font files and I need to do that from within the python environment. Yet, Fonttools is very poorly documented and I cannot find a module and the proper function syntax to perform subsetting based on unicode from within python, not as a command line tool (<code>pyftsubset</code>). Some of my files contain various errors when read by the Fonttools and I cannot catch exceptions using <code>!command</code> inside jupyter.</p>