Ah, I vaguely remember the LibDems - they used to be a political party at one time - I think I even voted for them once or twice.
The current LibDem leader said that if we elect a LibDem government
then they will prevent Brexit.
Presumably some clever LibDem has invented a time machine, so that once they are elected and Brexit has already happened they can travel back in time to prevent it. Maybe they'll seek out BoJo's and Farage's mothers and arrange to prevent them being impregnated during the necessary week or so.