Incorrect AES key length (12 bytes)

[yashkhare0]

Cannot fix this ValueError in utils.py

File "C:\Users\yashk\Dev\ecom\env\lib\site-packages\django\core\handlers\exception.py", line 34, in inner
response = get_response(request)
File "C:\Users\yashk\Dev\ecom\env\lib\site-packages\django\core\handlers\base.py", line 115, in _get_response
response = self.process_exception_by_middleware(e, request)
File "C:\Users\yashk\Dev\ecom\env\lib\site-packages\django\core\handlers\base.py", line 113, in _get_response
response = wrapped_callback(request, *callback_args, **callback_kwargs)
File "C:\Users\yashk\Dev\ecom\env\lib\site-packages\django\views\generic\base.py", line 71, in view
return self.dispatch(request, *args, **kwargs)
File "C:\Users\yashk\Dev\ecom\env\lib\site-packages\django\utils\decorators.py", line 43, in _wrapper
return bound_method(*args, **kwargs)
File "C:\Users\yashk\Dev\ecom\env\lib\site-packages\django\views\decorators\csrf.py", line 54, in wrapped_view
return view_func(*args, **kwargs)
File "C:\Users\yashk\Dev\ecom\env\lib\site-packages\django\contrib\auth\mixins.py", line 52, in dispatch
return super().dispatch(request, *args, **kwargs)
File "C:\Users\yashk\Dev\ecom\env\lib\site-packages\django\views\generic\base.py", line 97, in dispatch
return handler(request, *args, **kwargs)
File "C:\Users\yashk\Dev\ecom\env\lib\site-packages\django\views\generic\base.py", line 158, in get
context = self.get_context_data(**kwargs)
File "C:\Users\yashk\Dev\ecom\paytm\views.py", line 53, in get_context_data
'CHECKSUMHASH': generate_checksum(ctx['paytm_req_data'], settings.PAYTM_MERCHANT_KEY)
File "C:\Users\yashk\Dev\ecom\paytm\utils.py", line 23, in generate_checksum
return encode(hash_string, IV, merchant_key)
File "C:\Users\yashk\Dev\ecom\paytm\utils.py", line 108, in encode
c = AES.new(key.encode('utf-8'), AES.MODE_CBC, iv.encode('utf-8'))
File "C:\Users\yashk\Dev\ecom\env\lib\site-packages\Crypto\Cipher\AES.py", line 232, in new
return create_cipher(sys.modules[name], key, mode, *args, **kwargs)
File "C:\Users\yashk\Dev\ecom\env\lib\site-packages\Crypto\Cipher_init.py", line 79, in _create_cipher
return modes[mode](factory, **kwargs)
File "C:\Users\yashk\Dev\ecom\env\lib\site-packages\Crypto\Cipher_mode_cbc.py", line 274, in _create_cbc_cipher
cipher_state = factory._create_base_cipher(kwargs)
File "C:\Users\yashk\Dev\ecom\env\lib\site-packages\Crypto\Cipher\AES.py", line 93, in _create_base_cipher
raise ValueError("Incorrect AES key length (%d bytes)" % len(key))
ValueError: Incorrect AES key length (12 bytes)