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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 mkdtemp(suffix="", prefix=template, dir=None):
 """User-callable function to create and return a unique temporary directory. The return value is the pathname of the directory. Arguments are as for mkstemp, except that the 'text' argument is not accepted. The directory is readable, writable, and searchable only by the creating user. Caller is responsible for deleting the directory when done with it. """


    if dir is None:
        dir = gettempdir()

    names = _get_candidate_names()

    for seq in range(TMP_MAX):
        name = next(names)
        file = _os.path.join(dir, prefix + name + suffix)
        try:
            _os.mkdir(file, 0o700)
            return file
        except FileExistsError:
            continue    # try again

    raise FileExistsError(_errno.EEXIST,
                          "No usable temporary directory name found")