Euclidian Algorithm in Python

def euclidianAlg(a, b):
    a0 = a
    b0 = b
    t0 = 0
    t = 1
    s0 = 1
    s = 0
    q = a0 / b0
    r = a0 - q * b0
    while r > 0:
        temp = t0 - q * t
        t0 = t
        t = temp
        temp = s0 - q * s
        s0 = s
        s = temp
        a0 = b0
        b0 = r
        q = a0 / b0
        r = a0 - q * b0
        if r > 0:
            gcd = r

    return s