def total_completion_time(schedule):
    """ 
    Computes the total completion time for a given schedule.
    
    Args:
        schedule (list): a list of jobs (node object) listed according to the schedule.
    
    Returns:
        sum_Cj (float): the total completion time of all jobs in schedule.
    """
    Cj = 0
    sum_Cj = 0
    for job in schedule:
        Cj += job.processing
        sum_Cj += Cj
    
    return sum_Cj