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Python Code Samples

Copy-ready Python snippets by topic and difficulty — short, focused, and runnable in the browser editor.

3 matches
Dictionaries & sets easy

How to Subtract Counters in Python for Bag Differences

Use the Counter class's subtraction operator to compute bag differences, removing items and counts that appear in one multiset but not the other.

collections counter bags
Python
from collections import Counter

def subtract_counters(bag1, bag2):
    """Return the difference of two Counters (bag1 - bag2)."""
    return bag1 - bag2

if __name__ == "__main__":
    inventory = Counter(apples=10, bananas=5, oranges=3)
    sold = Counter(apples=4, bananas=2, grapes=2)
    remaining = subtract_count…
14 0 Open
Reliability & rate limiting easy

How to Mock Daily and Monthly Quota Counters in Python

Track daily and monthly API call usage with automatic resets, quota checks, and limits using a Python class.

quota rate-limiting class
Python
import random
from datetime import datetime, timedelta


class QuotaCounter:
    def __init__(self, daily_limit=1000, monthly_limit=20000):
        self.daily_limit = daily_limit
        self.monthly_limit = monthly_limit
        self.daily_usage = 0
        self.monthly_usage = 0
        self.current_day = datetime.n…
17 0 Open
Observability & SRE easy

How to Build a Metrics Counter with Increment and Snapshot in Python

A simple dict-backed MetricsCounter class that increments named counters and returns a snapshot of the current values.

metrics counter observability
Python
class MetricsCounter:
    def __init__(self):
        self._metrics = {}

    def increment(self, key, delta=1):
        self._metrics[key] = self._metrics.get(key, 0) + delta

    def snapshot(self):
        return dict(self._metrics)


if __name__ == "__main__":
    counter = MetricsCounter()
    counter.increment("…
13 0 Open

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