code: def cleanup_branch(self, branch):
          
          set_state(WORKFLOW_STATES.REMOVING_BACKPORT_BRANCH)
          self.checkout_default_branch()
          try:
              self.delete_branch(branch)
          except subprocess.CalledProcessError:
              click.echo(f"branch {branch} NOT deleted.")
              set_state(WORKFLOW_STATES.REMOVING_BACKPORT_BRANCH_FAILED)
          else:
              click.echo(f"branch {branch} has been deleted.")
              set_state(WORKFLOW_STATES.REMOVED_BACKPORT_BRANCH)
docs: Remove the temporary backport branch.
  
          Switch to the default branch before that.