Remove all occurrence of the parameter.
        :param item: Value to delete from the WeakList.

def remove_all(self, item):
        # type: (Any) -> None
        """
        Remove all occurrence of the parameter.
        :param item: Value to delete from the WeakList.
        """
        item = self.ref(item)
        while list.__contains__(self, item):
            list.remove(self, item)