If you're ok with just deleting the lines, a text editor is probably the fastest way to do this.
In an advanced editor like notepad++ (if you're using windows) you can very simply find all lines starting with 2 by searching for '^2' and delete them.
In an advanced editor like notepad++ (if you're using windows) you can very simply find all lines starting with 2 by searching for '^2' and delete them.