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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 normalize_drive(path):
 """Normalize drive in path so they stay consistent. This currently only affects local drives on Windows, which can be identified with either upper or lower cased drive names. The case is always converted to uppercase because it seems to be preferred. See: <https://github.com/pypa/pipenv/issues/1218> """

    if os.name != "nt" or not isinstance(path, six.string_types):
        return path

    drive, tail = os.path.splitdrive(path)
    # Only match (lower cased) local drives (e.g. 'c:'), not UNC mounts.
    if drive.islower() and len(drive) == 2 and drive[1] == ":":
        return "{}{}".format(drive.upper(), tail)

    return path