如何从 Python3 中的 input() 获取字节数组？

Question

I trying to make pretty simple script to decode bytes to UUID.

I have byte arrays like \223ge\254\367\217F\303\206\363\313H\222\207\362\216

I want to run python3 script from terminal, paste to input this array and see printed result of this code:

b_str = b'\223ge\254\367\217F\303\206\363\313H\222\207\362\216'
    print(UUID(bytes=b_str))

This example works fine and gives me this:
936765ac-f78f-46c3-86f3-cb489287f28e

But when I trying to write down and run something like this:

from uuid import UUID


def encode_client_id():
    bytes_str = input('Paste bytes string from decoded blob here: ')
    print(UUID(bytes=bytes_str))


if __name__ == '__main__':
    encode_client_id()

I always get this exception:

(venv) username@machinename:$ python3 main.py 
Paste bytes string from decoded blob here: \223ge\254\367\217F\303\206\363\313H\222\207\362\216
Traceback (most recent call last):
  File "main.py", line 11, in <module>
    encode_client_id()
  File "main.py", line 7, in encode_client_id
    print(UUID(bytes=bytes_str))
  File "/usr/lib/python3.8/uuid.py", line 178, in __init__
    raise ValueError('bytes is not a 16-char string')
ValueError: bytes is not a 16-char string
(venv) username@machinename:~/digitex/Dev/client_id_parser$ 

I understand that input() function always return string type, but I can't find any info how to convert string to bytes or take from input (terminal especially) byte array.

When I trying this code to transform string to bytes (with the same bytes array pasted to input):

bytes_str = input('Paste bytes string from decoded blob here: ')
    bytes_str = bytes(bytes_str, encoding='utf-8')
    print(bytes_str)

I get this:

Paste bytes string from decoded blob here: \223ge\254\367\217F\303\206\363\313H\222\207\362\216
b'\\223ge\\254\\367\\217F\\303\\206\\363\\313H\\222\\207\\362\\216'
Traceback (most recent call last):
  File "main.py", line 12, in <module>
    encode_client_id()
  File "main.py", line 8, in encode_client_id
    print(UUID(bytes=bytes_str))
  File "/usr/lib/python3.8/uuid.py", line 178, in __init__
    raise ValueError('bytes is not a 16-char string')
ValueError: bytes is not a 16-char string

Please help yet another newbie who can't handle simple issue:)

Answer 1

Surely there is a better way, but this is the best I can come up with for the moment:

from ast import literal_eval
from uuid import UUID

def encode_client_id():
    bytes_str = input('Paste bytes string from decoded blob here: ')
    bytes_str = literal_eval(f"b'{bytes_str}'")
    print(UUID(bytes=bytes_str))

>>> encode_client_id()
Paste bytes string from decoded blob here: \223ge\254\367\217F\303\206\363\313H\222\207\362\216
936765ac-f78f-46c3-86f3-cb489287f28e

This wraps the input string in quotes and prepends a b character to make the input a Python literal byte string. Then it calls literal_eval() on the doctored string to convert to an actual byte string that will be accepted by UUID() .

There must be something better?