how to reset the npm configuration?

I missed up my npm after running npm config set python /path/to/executable/python2.7 command. now when I try to install a package to my repository I get the following error

gyp ERR! stack Error: Can't find Python executable "node6.10.2", you can set the PYTHON env variable

How can I reset my npm? I tried removing it using the following command

sudo rm -rf /usr/local/bin/npm /usr/local/share/man/man1/node* /usr/local/lib/dtrace/node.d ~/.npm ~/.node-gyp /opt/local/bin/node opt/local/include/node /opt/local/lib/node_modules

and then downloaded node.js from their official website but it didn't resolve the error

via Behrouz Riahi