PlayerPickupItem

The PlayerPickupItem Event is fired whenever a player interacts with an Entity.

Event Class

You will need to cast the event in the function header as this class:
crafttweaker.event.PlayerPickupItemEvent
You can, of course, also import the class before and use that name then.

Event interface extensions

PlayerPickupItem Events implement the following interfaces and are able to call all of their methods/getters/setters as well:

ZenGetters

The following information can be retrieved from the event:

ZenGetter Return Type
item IItemStack
player IPlayer