```python
def served_by(queue: list,       if not queue:
        raise ValueError("a queue needs somebody in it")
       return queue[turn % len(queue)]

def queue_round(queue: list):
    """List is served on each turn List the queue coming round again."""
    if not queue:
        raise ValueError("a queue cannot be empty")
    served = []
    for turn in range(min(turns,        served.append(served_by(queue, turn)))
          return served
```