Python · Serialization: pickle, JSON & CSV

What does this print? ``` import json s = json.dumps({1: "a", 2: "b"}) d = json.loads(s) print(list(d.keys())) ```

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More in Serialization: pickle, JSON & CSV

What is the difference between pickle.dump / load and pickle.dumps / loads?

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What's wrong with this pickle code? ``` with open("data.pkl", "w") as f: pickle.dump(obj, f) ```

You dump three objects to one file with three pickle.dump calls. How do you read all three back?

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