npm降级后node不兼容报错

You are likely using a version of node-tar or npm that is incompatible with this version of Node.js.
Please use either the version of npm that is bundled with Node.js, or a version of npm (> 5.5.1 or < 5.4.0) or node-tar (> 4.0.1) that is compa
tible with Node.js 9 and above.

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解决办法： 

1.npm uninstall -g npm

2.npm install -g npm