寻找两个有序数组的中位数

def func(num1,num2):
    ret=0
    result=[]
    result.extend(num1)
    result.extend(num2)
    result.sort()
    if len(result)%2==0:
        index=int(len(result)/2)
        ret=(result[index-1]+result[index])/2
    else:
        index=int(len(result)/2)
        ret=result[index]
    return ret

ret=func([1,2],[3,4])
print(ret)