Stanislav Terliakov sterliakov
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| { | |
| "version":"2.0", | |
| "metadata":{ | |
| "apiVersion":"2006-03-01", | |
| "checksumFormat":"md5", | |
| "endpointPrefix":"s3", | |
| "globalEndpoint":"s3.amazonaws.com", | |
| "protocol":"rest-xml", | |
| "serviceAbbreviation":"Amazon S3", | |
| "serviceFullName":"Amazon Simple Storage Service", |
sterliakov
/ hashable_mutable.py
Created
July 23, 2022 00:14
Example of unexpected results with mutable hashable objects
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| class MyDict(dict): | |
| def __hash__(self): | |
| return hash(frozenset(self)) | |
| key = MyDict(a=1) | |
| mapping = {key: 'foo'} | |
| key['b'] = 2 | |
| mapping[key] # KeyError: {'a': 1, 'b': 2} | |
| # Do you expect that variable which you have added to dict would raise KeyError? |