'Checks so this player is actually listening
to this channel.
Args:
subscriber (Player or Object): Entity to check.
Returns:
has_sub (bool): Whether the subscriber is subscribing to
this channel or not.
Notes:
This will first try Player subscribers and only try Object
if the Player fails.'

def has_connection(self, subscriber):

    has_sub = self.subscriptions.has(subscriber)
    if ((not has_sub) and hasattr(subscriber, 'player')):
        has_sub = self.subscriptions.has(subscriber.player)
    return has_sub
