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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def create_new(cls, mapreduce_id, shard_number):
 """Create new shard state. Args: mapreduce_id: unique mapreduce id as string. shard_number: shard number for which to create shard state. Returns: new instance of ShardState ready to put into datastore. """

    shard_id = cls.shard_id_from_number(mapreduce_id, shard_number)
    state = cls(key_name=shard_id,
                mapreduce_id=mapreduce_id)
    return state