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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_host_address(host=None, default_address=DEFAULT_HOST_IP):
 """ Returns the given host address. :param host: Host to retrieve the address. :type host: unicode :param default_address: Default address if the host is unreachable. :type default_address: unicode :return: Host address. :rtype: unicode """


    try:
        return unicode(socket.gethostbyname(host or socket.gethostname()),
                       Constants.default_codec,
                       Constants.codec_error)
    except Exception as error:
        return default_address