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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 glymurrc_fname():
 """Return the path to the configuration file. Search order: 1) current working directory 2) environ var XDG_CONFIG_HOME 3) $HOME/.config/glymur/glymurrc """


    # Current directory.
    fname = os.path.join(os.getcwd(), 'glymurrc')
    if os.path.exists(fname):
        return fname

    confdir = get_configdir()
    if confdir is not None:
        fname = os.path.join(confdir, 'glymurrc')
        if os.path.exists(fname):
            return fname

    # didn't find a configuration file.
    return None