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Python Code Samples

Medium snippets you can copy, study, and run in the browser editor.

4 matches
Errors & debugging medium

Implement circuit breaker open after failures demo in Python

A minimal CircuitBreaker class that calls a function and automatically 'opens' after a set number of consecutive failures, blocking further calls with a RuntimeError.

circuit-breaker resilience error-handling
Python
import time
from datetime import datetime


class CircuitBreaker:
    def __init__(self, threshold=3):
        self.threshold = threshold
        self.failure_count = 0
        self.is_open = False

    def call(self, func, *args, **kwargs):
        if self.is_open:
            raise RuntimeError("Circuit is OPEN")
  …
13 0 Open
Algorithms & data structures medium

Find Longest Consecutive Sequence in Python

Find the length of the longest consecutive elements sequence in an unsorted array using a set for O(n) lookups.

set longest-sequence hash-table
Python
def longest_consecutive_length(nums):
    num_set = set(nums)
    longest = 0
    
    for num in num_set:
        if num - 1 not in num_set:
            current = num
            current_streak = 1
            
            while current + 1 in num_set:
                current += 1
                current_streak += 1
…
13 0 Open
Reliability & rate limiting medium

Circuit breaker failure threshold count in Python

Track consecutive or time-windowed failures with a deque to open a circuit breaker and auto-recover to half-open after a cooldown.

circuit-breaker resilience deque
Python
from collections import deque
from time import time, sleep


class CircuitBreaker:
    def __init__(self, failure_threshold: int = 5, recovery_time: float = 10.0):
        self.failure_threshold = failure_threshold
        self.recovery_time = recovery_time
        self.failures: deque[float] = deque()
        self.st…
16 0 Open
Reliability & rate limiting medium

Implement a Circuit Breaker Pattern in Python

This code implements a simple circuit breaker that opens after a threshold of consecutive failures, causing subsequent calls to fail fast without invoking the underlying function.

circuit-breaker reliability resilience
Python
class CircuitBreaker:
    def __init__(self, failure_threshold=3):
        self.failure_threshold = failure_threshold
        self.failure_count = 0
        self.open = False

    def call(self, func, *args, **kwargs):
        if self.open:
            raise RuntimeError("Circuit is open - failing fast")
        try:
…
15 0 Open

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