greenhat | Quick hack for making real work happen | Data Visualization library

Using an Array is very cumbersome since it is very difficult to rewrite a whole new value to it. Also why go through the necessity of converting from a dictionary to a string and back just to use an Array? Finally, any structure you wish to share between processes should be created by an a "manager" instance created by a call to multiprocessing.Manager() unless you want to manage the synchronization yourself.

The easiest way to accomplish your goal is to have the manager create two Queue objects, an input queue (for the input to your process) and an output queue to hold the result. In this particular case you could use the same queue object for both, but this is cleaner and is generally what you would use when you had multiple inputs and outputs being processed simultaneously by a pool of processes and you weren't using a standard library module such as multiprocessing.pool or concurrent.futures.

Finally, your construction of your Process subclass requires a bit of tweaking (your constructor need to call the base class constructor and should not call run). It's also usual to name your classes with a capital letter, although I left the name unchanged. I also think it's more usual not to subclass Process. Generally one just writes a function and passes to the call to Process target, args and/or kwargs parameters.

Update to Use a Managed Dictionary