Work on implementing backfill strategy - implement shadow_time function

], globals())

def shadow_time(queue):

    first_job = queue[0]  

    # Sort jobs according to their termination time (end_time)

    sorted_queue = sorted(queue, key=lambda job: job.end_time)

    # Loop over the list and collect nodes until the number of available nodes

    # is sufficient for the first job in the queue 

    sum_nodes = 0

    shadow_time = None

    for job in sorted_queue:

        sum_nodes += job.nodes_required

        if sum_nodes >= first_job.nodes_required:

            shadow_time = job.end_time

            break

    return shadow_time

def find_backfill_job(queue):

    pass

@dataclasses.dataclass

class TickData:

    """ Represents the state output from the simulation each tick """