Generating uniform random bits for iid binary source

uniform.py

class bitstream:
    def __init__(self, emit):
        self.emit = emit
        self.bits = []
        self.daughters = [None, None]
    def daughter(self, num):
        if self.daughters[num] is None:
            self.daughters[num] = bitstream(self.emit)
        return self.daughters[num]
    def send(self, bit):
        self.bits.append(bit)
        if len(self.bits) < 2:
            return
        a, b = self.bits[0], self.bits[1]
        self.bits = []
        if a == b:
            self.daughter(0).send(a)
            self.daughter(1).send(0)
        else:
            self.emit(a)
            self.daughter(1).send(1)

import random
            
def test(p, n, seed = None):
    output = []
    random.seed(seed)
    bs = bitstream(lambda x: output.append(x))
    for _ in xrange(n):
        bs.send(int(random.random() < p))
    return output