python int binary

1print('{0:b}'.format(3))        # '11'
2print('{0:8b}'.format(3))       # '      11'
3print('{0:08b}'.format(3))      # '00000011'
4
5def int2bin(integer, digits):
6    if integer >= 0:
7        return bin(integer)[2:].zfill(digits)
8    else:
9        return bin(2**digits + integer)[2:]
10print(int2bin(3, 6))            # '000011'