.npz is not utf-8 encoded

The .npz file format is not a text-based format, but a binary format used for storing arrays and other data in NumPy. Therefore, it is not encoded using UTF-8 or any other text encoding. If you encounter an error message stating that a .npz file is not UTF-8 encoded, it may be due to a problem with the way the file is being read or processed, such as trying to open it as a text file. You may need to use a specific library or tool designed for working with .npz files to properly read and process the data.