How can I speed up this project Euler Q#35 solution?

How can I speed up this code? It takes too long if I run it with standard python interpreter. However, I am able to reduce execution time to 13 seconds by running in "pypy" interpreter.

Project Euler problem:

The number, 197, is called a circular prime because all rotations of the digits: 197, 971, and 719, are themselves prime. There are thirteen such primes below 100: 2, 3, 5, 7, 11, 13, 17, 31, 37, 71, 73, 79, and 97. How many circular primes are there below one million?

from collections import deque

def sieve(limit):
    nums = (True) * (limit+1)
    nums(0) = nums(1) = False

    for i, is_prime in enumerate(nums):
        if is_prime:
            yield i
            for n in range(i*i, limit+1, i):
                nums(n) = False

def rotations(n):
    l = deque(list(str(n)))
    r = ()

    for _ in range(len(l)):
    return r

def circular_prime(n):
    cp = ()
    s = list(sieve(n))
    for i in s:
        r = rotations(i)
        flags = (False) * len(r)
        for k, j in enumerate(r):
            if j in s:
                flags(k) = True
        if all(flags):
    return len(cp)