Fix B018 (useless expression)

Author: akx

bitsandbytes/cextension.py

@@ -22,7 +22,7 @@
         Inspect the output of the command and see if you can locate CUDA libraries. You might need to add them
         to your LD_LIBRARY_PATH. If you suspect a bug, please take the information from python -m bitsandbytes
         and open an issue at: https://github.com/TimDettmers/bitsandbytes/issues''')
-    lib.cadam32bit_grad_fp32 # runs on an error if the library could not be found -> COMPILED_WITH_CUDA=False
+    _ = lib.cadam32bit_grad_fp32  # runs on an error if the library could not be found -> COMPILED_WITH_CUDA=False
     lib.get_context.restype = ct.c_void_p
     lib.get_cusparse.restype = ct.c_void_p
     lib.cget_managed_ptr.restype = ct.c_void_p