How to convert string from UCS2 to readable text

Question

I need to convert the given string from UCS2 to readable text. How can I implement this in Python and C++ Arduino without using third-party modules.

st ="041204410451002004210443043F04350440003A00200031003300200413041100200438043D044204350440043D043504420430002C00200031003500300020043C0438043D00200030002004410435043A0020043D04300020043C043E04310438043B044C043D044B043500200420041A00200434043E002000320037002E00300038002E00320032"

I found this code, but it does not work as it should. Can you please tell me how to do the correct calculation?

def con():
    UCS2ToChar = ''
    res = ""
    arrUCS2 = list("0412")

    if (arrUCS2[1] == '4'):
        if (arrUCS2[2] == '0'): UCS2ToChar = 89
        elif (arrUCS2[2] == '1'): UCS2ToChar = 64
        elif (arrUCS2[2] == '2'): UCS2ToChar = 48
        elif (arrUCS2[2] == '3'): UCS2ToChar = 32
        elif (arrUCS2[2] == '4'): UCS2ToChar = 16
        elif (arrUCS2[2] == '4'): UCS2ToChar = 73

        if (int(arrUCS2[3]) > int('9')):
            UCS2ToChar -= (int(arrUCS2[3]) - 55)
        else:
            UCS2ToChar -= (int(arrUCS2[3]) - int('0'))
        UCS2ToChar = (int(UCS2ToChar))
        res += (chr(UCS2ToChar))
        print(res)
con()

If you do this print (ord ('B')) then the code of the letter (which, in theory, is encrypted there) will be different from that obtained using this enumeration.

Answer 1

Based on Python UCS2 decoding from hex string - Stack Overflow

import binascii

st = "041204410451002004210443043F04350440003A00200031003300200413041100200438043D044204350440043D043504420430002C00200031003500300020043C0438043D00200030002004410435043A0020043D04300020043C043E04310438043B044C043D044B043500200420041A00200434043E002000320037002E00300038002E00320032"

text = binascii.unhexlify(st).decode('utf-16-be')

print(text)

or

import codecs

st = "041204410451002004210443043F04350440003A00200031003300200413041100200438043D044204350440043D043504420430002C00200031003500300020043C0438043D00200030002004410435043A0020043D04300020043C043E04310438043B044C043D044B043500200420041A00200434043E002000320037002E00300038002E00320032"

text = codecs.decode(st, 'hex').decode('utf-16-be') 

print(text)

Result:

Всё Супер: 13 ГБ интернета, 150 мин 0 сек на мобильные РК до 27.08.22

binascii and codecs are standard modules preinstalled with Python.