def yml_part(part, *files):
    yml = ('- part: %s\n  chapters:\n' % part)
    for file in files:
        yml += ('  - file: %s\n' % file)
    return (yml + '\n')
def yml_part(part, *files):
    yml = ('- part: %s\n  chapters:\n' % part)
    for file in files:
        yml += ('  - file: %s\n' % file)
    return (yml + '\n')