Reading binary data

[Aaron Scott]

> signature, version, attr_count = struct.unpack('3cII',
> yourfile.read(11))
>

This line is giving me an error:

Traceback (most recent call last):
  File "test.py", line 19, in <module>
    signature, version, attr_count = struct.unpack('3cII',
file.read(12))
ValueError: too many values to unpack