Use DictTuple(tuple) for Dataset.assets and SyftClient.datasets instead of TupleDict(OrderedDict)

[kiendang]

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[madhavajay]

@kiendang interesting. Lets discuss in the Eng channel in slack.

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[madhavajay]

@kiendang great work, I had a play and found a possible bug.

It seems if the keys are ints and non 0 sequential it freaks out on casting to a dict.

[madhavajay]

Great work. The feel of using this is nice when indexing with both string or int keys.

Its a little complex to understand at first read and this kind of code often can hide bugs because its so complicated but the tests definitely help. Can you fix the non zero sequential int keys issue I found and then I think we can merge it. 🙌

[kiendang]

@madhavajay Yah keys should not be int. If you have a d: DictTuple with int keys, now d[2] is ambiguous since it means both "getting the 3rd element" and "getting the element with key 2". I'll just put in a check, raising an error on attempting to create a DictTuple with int key.

You would encounter similar error with the current TupleDict too.

p = TupleDict({1: "z", 2: "b"})
p[2]

File "/Users/kien/pysyft/packages/syft/src/syft/types/tupledict.py", line 14, in __getitem__
    return list(self.values())[key]
           ~~~~~~~~~~~~~~~~~~~^^^^^
IndexError: list index out of range

the tests definitely help

I have a more comprehensive test suite for this but is currently blocked by #8188 (without #8188 it is very slow). Will push that once it is resolved.