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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def main():
 """1. Parse args 2. Figure out which directories are actually meraculous run directories 3. Make an instance for each directory and generate a report """

    home = os.getcwd()
    options = parse_arguments()
    print(options)
    print()

    #get a list of all directories in the cwd
    dirs = [direc for direc in os.listdir(home) if os.path.isdir(direc)]
    #instantiate all of the classes that we will be using in parallel processing
    instances = []
    for each in dirs:
        thisInstance = meraculousRunAnalyzer(each, options.censor, options.quiet)
        #only process the instances that are meraculous directories
        if thisInstance.isMer:
            instances.append(thisInstance)

    if len(instances) == 0:
        print("There are no meraculous folders in this directory. Exiting")
    elif len(instances) > 0:
        # run the program for each instance
        #process each file sequentially using max number of threads
        #determine the pool size to work with the unique sample names
        pool_size = determine_pool_size(instances)
        pool = ThreadPool(pool_size)
        results = pool.map(run_merReport_dummy, instances)
        pool.close()
        pool.join()