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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 _execute_cmd(plugin, args='', run_type='cmd.retcode'):
    '''
    Execute nagios plugin if it's in the directory with salt command specified in run_type
    '''
    data = {}

    all_plugins = list_plugins()
    if plugin in all_plugins:
        data = __salt__[run_type](
                '{0}{1} {2}'.format(PLUGINDIR, plugin, args),
                python_shell=False)

    return data