Add rate limiting code

implementations/python/rate_limiting/token_bucket.py

@@ -0,0 +1,31 @@
+import time
+
+class TokenBucket:
+    def __init__(self, capacity, fill_rate):
+        self.capacity = capacity  # Maximum number of tokens the bucket can hold
+        self.fill_rate = fill_rate  # Rate at which tokens are added (tokens/second)
+        self.tokens = capacity  # Current token count, start with a full bucket
+        self.last_time = time.time()  # Last time we checked the token count
+
+    def allow_request(self, tokens=1):
+        now = time.time()
+        # Calculate how many tokens have been added since the last check
+        time_passed = now - self.last_time
+        self.tokens = min(self.capacity, self.tokens + time_passed * self.fill_rate)
+        self.last_time = now
+
+        # Check if we have enough tokens for this request
+        if self.tokens >= tokens:
+            self.tokens -= tokens
+            return True
+        return False
+
+# Usage example
+limiter = TokenBucket(capacity=10, fill_rate=1)  # 10 tokens, refill 1 token per second
+
+for _ in range(15):
+    print(limiter.allow_request())  # Will print True for the first 10 requests, then False
+    time.sleep(0.1)  # Wait a bit between requests
+
+time.sleep(5)  # Wait for bucket to refill
+print(limiter.allow_request())  # True