'Callback to handle the start of a list
`key` is the redis key for this list
`expiry` is a `datetime` object. None means the object does not expire
`info` is a dictionary containing additional information about this object.
After `start_list`, the method `rpush` will be called with `key` exactly `length` times
After that, the `end_list` method will be called to indicate the end of the list
Note : This callback handles both Zip Lists and Linked Lists.'

def start_list(self, key, expiry, info):

    pass
