AttributeError: 'str' object has no attribute 'decode'. Did you mean: 'encode'?

[ged-flod]

When using this exmple from README.md

from smshelper import SMSHelper
sms = SMSHelper('Sample message.')

sms.detect_encoding() # return 'GSM_7BIT'

sms.count() # return : AttributeError: 'str' object has no attribute 'decode'. Did you mean: 'encode'?

sms.parts() # return : AttributeError: 'str' object has no attribute 'decode'. Did you mean: 'encode'?

Python version 3.12.7
MacOs Sequoia version 15.0.1