Implementing a Promise Class | Dataford Interview Questions

Write promise class from scratch.

Implement a Python function that defines and exercises a Promise-like abstraction. It must support fulfillment, rejection, chaining with then, exception propagation, thenable assimilation, self-resolution protection, finally, and the all and race combinators.

Use the supplied scenario object as the grading contract. Return a plain dictionary containing the final state and either value or the exception type in error.

Function signature: def promise_class(scenario):

Constraints

scenario is a JSON-compatible dictionary with a valid kind field
chain operations contain only map, throw, or reject operations
all and race values are JSON-compatible primitive values
Promise settlement is one-way
The returned dictionary must contain only JSON-compatible values

Function Signature

def promise_class(scenario):

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