def init(queue):
    """
    This is a wrapper script to be called by the 'multiprocessing.map' function
    to calculate the model functions in parallel.

    This function will be called upon initialization of the process.
    It sets a global variable denoting the ID of this process that can
    be read by any function of this process

    Parameters
    ----------
    queue : multiprocessing.Queue
             the queue object that manages the unique IDs of the process pool
    """
    global process_id
    process_id = queue.get()
