Are you suggesting just taking the read_and_process_file function out of the read_dataset method, or maybe decoupling the read_dataset method from the NetCDFReader class so it is not pickle along with the class instance itself?

As for the second option, you mean create the task in the __init__ method of the NetCDFReader class?

It would be a great idea to make the Task picklelizable, since at the moment what are the most frequently used options for integrating multiprocessing tasks in scripts that include Task.init ?