问pymedia中的MuxerError

EN

Traceback (most recent call last):
  File "C:/Users/tryer.py", line 7, in <module>
    da=dm.getInfo()
MuxerError: The header has not been read yet. Cannot get stream information.

    import glob
    import pymedia
    for x in glob.glob('C:\Downloaded/*mp3'):


        dm=pymedia.muxer.Demuxer( str.split( x, '.' )[ -1 ].lower() )
        da=dm.getInfo()
        print da
        a=da('title')