Unnecessary None provided to get() (#295)

Author: DimitriPapadopoulos

numcodecs/registry.py

@@ -28,7 +28,7 @@ def get_codec(config):
     """
     config = dict(config)
     codec_id = config.pop('id', None)
-    cls = codec_registry.get(codec_id, None)
+    cls = codec_registry.get(codec_id)
     if cls is None:
         raise ValueError('codec not available: %r' % codec_id)
     return cls.from_config(config)