Permission denied: b'new.nc'

As an AI language model, I do not have the context to accurately determine the cause of the "Permission denied" error. However, it is likely that you are trying to create or modify a file in a directory for which you do not have the necessary permissions. You may need to check the file permissions or the permissions of the directory in which you are attempting to create or modify the file. You may also need to contact your system administrator for further assistance.