How to Build a Shard Map Mock Dict in Python

class ShardMap:
    def __init__(self, shard_count):
        self.shards = {i: {} for i in range(shard_count)}
        self.shard_count = shard_count

    def _shard_for(self, key):
        return hash(key) % self.shard_count

    def __getitem__(self, key):
        return self.shards[self._shard_for(key)][key]

    def __setitem__(self, key, value):
        self.shards[self._shard_for(key)][key] = value

    def __delitem__(self, key):
        del self.shards[self._shard_for(key)][key]

    def __contains__(self, key):
        shard = self.shards[self._shard_for(key)]
        return key in shard

    def __len__(self):
        return sum(len(shard) for shard in self.shards.values())

    def get(self, key, default=None):
        return self.shards[self._shard_for(key)].get(key, default)

    def keys(self):
        return [key for shard in self.shards.values() for key in shard]

    def __repr__(self):
        return f"ShardMap(shards={self.shards})"


if __name__ == "__main__":
    smap = ShardMap(shard_count=3)
    smap["apple"] = 10
    smap["banana"] = 20
    smap["cherry"] = 30

    print(smap["banana"])
    print(len(smap))
    print(smap.keys())
    print("apple" in smap)
    print(smap.shards)