Hostile Mob Repellent

What: A new item called Mob Repellent. This would be an item that causes all hostile mobs not to attack the player when it is the hotbar of the player's inventory. The item would be unavailable without the use of commands, or it would be a post-game item which is extremely difficult to craft, to avoid reducing the difficulty of gameplay.

What problem are you solving: Some players like to play survival without fighting mobs (peaceful mode), while others like to play it with fighting. If both types of players want to play in a realm or personal server together at the same time, there is currently no way to do this. This item would make it easy, as the server/realm owner could just use commands to give a mob repellent to all the players who want one, while the others still get to fight mobs as normal.

Why you want it done: I'm actually one of those players mentioned above that likes peaceful mode, my friend has recently created a server and I just want to go out and explore the world, gather items and build stuff, but I keep getting swooped, slashed and shot at by mobs whenever I try to. My friends like all that stuff, so I can't ask them to turn it off or they won't enjoy the game, but at the same time, I can't enjoy the game right now. It'd be great if we had a way to both play together, and I'm sure I'm not the only one who has been in a similar situation.

How you want it done: The item would effectively tell any mobs to treat the player holding it as if that player were in creative mode. In all other respects, the player will still be in survival mode, they still have limited health, hunger, limited resources, etc. Just mobs won't attack them. The mobs will still attack other nearby players, just not the player who has the item in their hotbar.