very light refactor of the py3k PR

Author: jiaaro

pydub/audio_segment.py

@@ -127,7 +127,7 @@ def __init__(self, data=None, *args, **kwargs):
                 setattr(self, attr, val)
         else:
             # normal construction
-            data = data if isinstance(data, basestring) or isinstance(data, bytes) else data.read()
+            data = data if isinstance(data, (basestring, bytes)) else data.read()
             raw = wave.open(StringIO(data), 'rb')
 
             raw.rewind()