Dangers of Python Lambda: Repeated Values due to Late Binding

Avoid hidden bugs due to unexpected values in loops with AsyncIO or Multi-threading Python.

There may be a scary secret problem in your use of lambda in Python, when used with AsyncIO or Multi-threading. It is called Late Binding.

The Question

Can you see what is unexpected about below results of the DocTest? By the way, you are familiar with add_done_callback method, right?

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