Decoder.open doesn't work

Hello!

I have been trying for several days to get things running on my Raspberry Pi 4B.

However, I keep getting the following error message:

self.music_file = decoder.open(self.song_filename, force_header)

^^^^^^^^^^^^

AttributeError: module 'decoder' has no attribute 'open'

When I check it in python3, I see:

>> import decoder

>>> dir(decoder)

['__builtins__', '__cached__', '__doc__', '__file__', '__loader__', '__name__', '__package__', '__path__', '__spec__']

>>>

Has anyone had this happen, please? Any suggestions much appreciated.

Thanks,

Erin