请编写一个函数实现将IP地址转换成一个整数

ip = '192.168.12.87'

lst = ip.split('.')
for i in range(len(lst)):
    s = bin(int(lst[i]))
    print(s)    # 0b11000000   0b10101000   0b1100   0b1010111
    lst[i] = s[2:]
    print(lst)
    if len(lst[i]) < 8:
        s1 = '0'*(8-len(lst[i])) + lst[i]
        lst[i] = s1
val = ''.join(lst)
print(val)
print(int('0b' + val,base=2))