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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 init_dirs(rootdir_or_loader, outputpath, saveto_dir='data', auximages_dir='auximages', prefix='crd'):
 """Initialize the directiories. Inputs: rootdir_or_loader: depends on the type: str: the root directory of the SAXSCtrl/CCT software, i.e. where the subfolders ``eval2d``, ``param``, ``images``, ``mask`` etc. reside. sastool.classes2.Loader instance: a fully initialized loader, which will be used to acquire headers and exposures. list: a list of sastool.classes2.Loader instances, which will be used to open headers and exposures. When opening something, always the first item will be tried first, and if it fails with FileNotFoundError, the second, third, etc. will be tried until either the file can be opened or the last one fails. outputpath: the directory where the produced files are written. This is usually the working directory of the IPython notebook. saveto_dir: the subdirectory where averaged, united, subtracted etc. datasets are written. auximages_dir: the subdirectory where automatically produced images reside. Remarks: If a single root directory is given, a list of four loaders will be constructed in this order: CCT (processed), CCT (raw), SAXSCtrl (processed), SAXSCtrl (raw). Raw and processed loaders are handled separately. """

    ip = get_ipython()
    if isinstance(rootdir_or_loader, str):
        print("Initializing loaders for SAXSCtrl and CCT.", flush=True)
        ip.user_ns['_loaders'] = [
            credo_cct.Loader(rootdir_or_loader, processed=True, exposureclass=prefix),
            credo_saxsctrl.Loader(rootdir_or_loader, processed=True, exposureclass=prefix),
            credo_cct.Loader(rootdir_or_loader, processed=False, exposureclass=prefix),
            credo_saxsctrl.Loader(rootdir_or_loader, processed=False, exposureclass=prefix),
        ]
        print("Loaders initialized.", flush=True)
    elif isinstance(rootdir_or_loader, Loader):
        ip.user_ns['_loaders'] = [rootdir_or_loader]
    elif isinstance(rootdir_or_loader, list) and all([isinstance(l, Loader) for l in rootdir_or_loader]):
        ip.user_ns['_loaders'] = rootdir_or_loader[:]
    else:
        raise TypeError(rootdir_or_loader)
    if not os.path.isdir(outputpath):
        os.makedirs(outputpath)
    print("Output files will be written to:", outputpath)
    os.chdir(outputpath)
    ip.user_ns['outputpath'] = outputpath
    if not os.path.isdir(os.path.join(ip.user_ns['outputpath'], saveto_dir)):
        os.mkdir(os.path.join(ip.user_ns['outputpath'], saveto_dir))
    if not os.path.isdir(os.path.join(ip.user_ns['outputpath'], auximages_dir)):
        os.mkdir(os.path.join(ip.user_ns['outputpath'], auximages_dir))
    ip.user_ns['auximages_dir'] = os.path.join(outputpath, auximages_dir)
    ip.user_ns['saveto_dir'] = os.path.join(outputpath, saveto_dir)
    ip.user_ns['saveto_dir_rel'] = saveto_dir
    ip.user_ns['auximages_dir_rel'] = auximages_dir
    ip.user_ns['crd_prefix']=prefix
    set_length_units('nm')