Convert .cap to .capx in Capella

convert.py

import os, os.path
import sys

SOURCE_DIR = r'c:\users\joost\documents\capella\voorbeelden'

# a few useful functions
output = lambda s, t='': messageBox(t, str(s))
change_ext = lambda fn, ext: os.path.splitext(fn)[0] + ext
copy_mtime = lambda src, tgt: os.utime(tgt, os.stat(src)[7:9])

output('Python version: %r\nCapella version: %r' % (sys.version_info, capVersion()), 'Versions')

def converter(new_ext, write_xml):
    def convert(source):
        target = change_ext(source, new_ext)
        if os.path.exists(target):
            return
        openScore(source)
        if not activeScore():
            return
        activeScore().write(target, xml=write_xml)
        closeActiveScore()
        copy_mtime(source, target)
    return convert

def convert_files(source_dir, source_extension, convert_function):
    source_files = [ os.path.join(root, filename)
                     for (root, directories, filenames) in os.walk(source_dir)
                     for filename in filenames
                     if filename.endswith(source_extension) ][:4]
    map(convert_function, source_files)

capx_to_cap = converter(new_ext='.cap', write_xml=0)
cap_to_capx = converter(new_ext='.capx', write_xml=1)

convert_files(SOURCE_DIR, '.cap', cap_to_capx)