Download the command here, to install just double-click on it.

To use it go to the your own bundle that the command has been installed in and make a key equivalent activation, I have mine set up for ^⌥⌘T.

Also while you’re in the Bundle Editor you need to put in your Twitter account login and password, on the 8th line replace your_username with your login username, and on the 9th line replace your_password with your password.