Why Does Python Dictionary Key Order Seem Random (But Isn\'t Always)?

Why Does Python Order Dictionaries in an Unpredictable Manner?

In Python, dictionaries are unordered data structures, meaning that the order of keys is not preserved. However, as the question highlights, even though dictionaries are unordered, they often return keys in the same order.

Older versions of Python employed hash tables in the implementation of dictionaries. Hash tables are efficient data structures that typically use hashing functions to determine key positions. The order of elements in a hash table is not immediately obvious but follows specific rules. In the case of the question, the observed output matches the rules of a hash table perfectly, resulting in an apparently arbitrary yet constant order.

With the release of Python 3.7, the implementation of dictionaries was revised to preserve the order of insertion. This change allows for guaranteed order, ensuring that the order of keys returned matches the order in which they were added to the dictionary.

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