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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 get_configdir():
 """Return string representing the configuration directory. Default is $HOME/.config/glymur. You can override this with the XDG_CONFIG_HOME environment variable. """

    if 'XDG_CONFIG_HOME' in os.environ:
        return os.path.join(os.environ['XDG_CONFIG_HOME'], 'glymur')

    if 'HOME' in os.environ and os.name != 'nt':
        # HOME is set by WinPython to something unusual, so we don't
        # necessarily want that.
        return os.path.join(os.environ['HOME'], '.config', 'glymur')

    # Last stand.  Should handle windows... others?
    return os.path.join(os.path.expanduser('~'), 'glymur')