'str' object has no attribute 'decode'

Question

I'm trying to decode hex string to binary values. I found this below command on internet to get it done,

string_bin = string_1.decode('hex')

but I got error saying

'str' object has no attrubute 'decode'

I'm using python v3.4.1

Answer 1

You cannot decode string objects; they are already decoded. You'll have to use a different method.

You can use the codecs.decode() function to apply hex as a codec:

>>> import codecs
>>> codecs.decode('ab', 'hex')
b'\xab'

This applies a Binary transform codec; it is the equivalent of using the base64.b16decode() function, with the input string converted to uppercase:

>>> import base64
>>> base64.b16decode('AB')
b'\xab'

You can also use the binascii.unhexlify() function to 'decode' a sequence of hex digits to bytes:

>>> import binascii
>>> binascii.unhexlify('ab')
b'\xab'

Either way, you'll get a bytes object.

Answer 2

Use binascii:

import binascii

binary_string = binascii.unhexlify(hex_string)