npm install ws fails on MacOS big sur

I tried to install websocket on MacOS via "npm install ws" in terminal. but it always returned

npm ERR! code ENOSELF

npm ERR! Refusing to install package with name "ws" under a package

npm ERR! also called "ws". Did you name your project the same

npm ERR! as the dependency you're installing?

npm ERR! 

npm ERR! For more information, see:

npm ERR!   <https://docs.npmjs.com/cli/install#limitations-of-npms-install-algorithm>

npm ERR! A complete log of this run can be found in:

npm ERR!   /Users/croydon/.npm/_logs/2021-03-18T00_55_40_611Z-debug.log