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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 set_config_file(name):
    '''
    Sets the configuration's name. This function is intended to be used from
    states.

    CLI Example:

    .. code-block:: bash

        salt '*' syslog_ng.set_config_file name=/etc/syslog-ng

    '''
    global __SYSLOG_NG_CONFIG_FILE
    old = __SYSLOG_NG_CONFIG_FILE
    __SYSLOG_NG_CONFIG_FILE = name
    changes = _format_changes(old, name)
    return _format_state_result(name, result=True, changes=changes)