Code reviewMediumcr-g429

Subject Thread safetyLevel Mid–Senior~24 minCommon in Concurrency interviewsIndustries Software development

Question

Review this Python in-memory rate counter shared across request threads (CPython, with the GIL).

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Separate real bugs from style. Rank issues by severity, point at the root cause rather than the symptom, and suggest a concrete fix — specific and kind.

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Code to reviewpython

1class Limiter:2    def __init__(self):3        self.counts = {}4 5    def allow(self, key, limit):6        n = self.counts.get(key, 0)7        if n >= limit:8            return False9        self.counts[key] = n + 110        return True

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