how to xor binary with python

a="11011111101100110110011001011101000"
b="11001011101100111000011100001100001"
y=int(a,2) ^ int(b,2)
print('{0:b}'.format(y))

To get the Xor'd binary to the same length, as per the OP's request, do the following:

a = "11011111101100110110011001011101000"
b = "11001011101100111000011100001100001"
y = int(a, 2)^int(b,2)
print bin(y)[2:].zfill(len(a))

[output: 00010100000000001110000101010001001]

Convert the binary strings to an integer base 2, then XOR, then bin() and then skip the first two characters, 0b, hence the bin(y0)[2:].
After that, just zfill to the length - len(a), for this case.

Cheers