import time


class TokenBucket:
    def __init__(self, rate, capacity):
        self.rate, self.capacity = rate, capacity
        self.tokens, self.stamp = capacity, time.monotonic()

    def take(self):
        now = time.monotonic()
        self.tokens = min(self.capacity, self.tokens + (now - self.stamp) * self.rate)
        self.stamp = now
        if self.tokens >= 1:
            self.tokens -= 1
            return True
        return False