#57MediumFunctions· Decorators

Function Decorators: Call Logger

A decorator wraps a function to add behaviour without changing the function's own code. Logging every call is the classic example. Complete the decorator factory `log_calls(log)`. It receives a list and returns a decorator; every function decorated with `@log_calls(log)` must, on each call: - call the original function with the same arguments; - on success, append `"<name>(<args>) -> <result>"` to `log` and return the result; - if the function raises, append `"<name>(<args>) raised <ExceptionType>"` and let the exception continue. `<args>` is the arguments separated by `", "`, each written with `repr()`. The wrapper must keep the original function's `__name__` (use `functools.wraps`). `run_logged(calls)` is already written in the starter code: it decorates `divide` (integer division) and `power`, makes the requested calls, ignores errors, and finally appends the names of the two decorated functions. You only need to complete `log_calls`.

Input format

`calls`: a list of `[function_name, a, b]` entries, where `function_name` is `"divide"` or `"power"`.

Output format

The log as a list of strings.

Examples

Input: calls = [["divide",7,2],["power",2,10]]

Output: ["divide(7, 2) -> 3","power(2, 10) -> 1024","decorated: divide, power"]

Both calls succeed and are logged with their results.

Input: calls = [["divide",1,0]]

Output: ["divide(1, 0) raised ZeroDivisionError","decorated: divide, power"]

Integer division by zero raises ZeroDivisionError; the wrapper logs it and re-raises, and `run_logged` ignores it.

Constraints

0 <= len(calls) <= 20
-100 <= a, b <= 100
power is only called with 0 <= b <= 10

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Functions in Python

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