Convert WIF to private key I am aware how to convert the private key into WIF format in python, now I am trying to reverse this process and convert a WIF formatted private key back into a 256-bit private key, following this guide: https://en.bitcoin.it/wiki/Wallet_import_format

This is the code to convert from 256-bit private key into WIF format:

import hashlib
import base58
import binascii


private_key_static = "0C28FCA386C7A227600B2FE50B7CAE11EC86D3BF1FBE471BE89827E19D72AA1D"
extended_key = "80"+private_key_static
first_sha256 = hashlib.sha256(binascii.unhexlify(extended_key)).hexdigest()
second_sha256 = hashlib.sha256(binascii.unhexlify(first_sha256)).hexdigest()

# add checksum to end of extended key
final_key = extended_key+second_sha256[:8]

# Wallet Import Format = base 58 encoded final_key
WIF = base58.b58encode(binascii.unhexlify(final_key))

print (WIF)


Now my attempt to reverse this process looks like this:

import hashlib
import base58
import binascii

private_key_WIF = 5HueCGU8rMjxEXxiPuD5BDku4MkFqeZyd4dZ1jvhTVqvbTLvyTJ
first_encode = base58.b58decode(binascii.hexlify(private_key_WIF))
print (first_encode)


Instead of receiving the byte string, I get following error: 

TypeError: a bytes-like object is required, not 'str'


(All private keys used are sample keys taken from Bitcoin Wiki.)
converts WIF private key back to basic private key format
import hashlib
import base58
import binascii

private_key_WIF = input(&quot;WIF: &quot;)
first_encode = base58.b58decode(private_key_WIF)
private_key_full = binascii.hexlify(first_encode)
private_key = private_key_full[2:-8]
print(private_key)