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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 show_driver(devname):
    '''
    Queries the specified network device for associated driver information

    CLI Example:

    .. code-block:: bash

        salt '*' ethtool.show_driver <devname>
    '''

    try:
        module = ethtool.get_module(devname)
    except IOError:
        log.error('Driver information not implemented on %s', devname)
        return 'Not implemented'

    try:
        businfo = ethtool.get_businfo(devname)
    except IOError:
        log.error('Bus information no available on %s', devname)
        return 'Not available'

    ret = {
        'driver': module,
        'bus_info': businfo,
    }

    return ret