<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def available():
 """ Returns list of available font names. """

    font_dir = os.path.dirname(__file__)
    names = [os.path.basename(os.path.splitext(f)[0])
            for f in glob(os.path.join(font_dir, '*.pil'))]
    return sorted(names)