Python is in the same situation, what Python coders do is span processes, in this case OS process which is an instance of python interpreter , the advantage of an OSprocess is that it can run on a separate core in case you have a multicore cpu. This way you get true concurrency. However OS process are isolated so you will have to make them communicate via sockets or pipes. Python has such libraries to facilitate easy communication between processes.
In case of Pharo you would be opening Pharo headless several times, one instance for each concurrent task you want. This way you will get non blocking code and able to take advantage of all the cores of your cpu. �