Evil and adding a binding for evil-ex-define-cmd globally for tabbar mode

Question

I’m using spacemacs:

•  How can I (globally —ie, permanently) bind a new command :tabe to open a new tab in the emacs built-in minor mode TabBar?

•  Right now, :tabnew works. But I want to make :tabe do the same thing as :tabnew

•  I see the following examples:

(when (featurep 'tab-bar)
  (evil-ex-define-cmd "tabnew" 'tab-bar-new-tab)
  (evil-ex-define-cmd "tabn[ext]" 'tab-bar-switch-to-next-tab)
  (evil-ex-define-cmd "tabp[revious]" 'tab-bar-switch-to-prev-tab))

But how do I execute these while in emacs? Ie, analogous functionality as doing M-x set-global-key