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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 _remote_folder(dirpath, remotes, syn):
 """Retrieve the remote folder for files, creating if necessary. """

    if dirpath in remotes:
        return remotes[dirpath], remotes
    else:
        parent_dir, cur_dir = os.path.split(dirpath)
        parent_folder, remotes = _remote_folder(parent_dir, remotes, syn)
        s_cur_dir = syn.store(synapseclient.Folder(cur_dir, parent=parent_folder))
        remotes[dirpath] = s_cur_dir.id
        return s_cur_dir.id, remotes