unicode problem

$ python3.6 unicodepython3.6 "j'ai réussi à écrire une version plus concise"
Traceback (most recent call last):
  File "unicodepython3.6", line 9, in <module>
    print(f"usertext was {usertext}")
UnicodeEncodeError: 'utf-8' codec can't encode characters in position 19-20: surrogates not allowed
$ cat unicodepython3.6
#!/usr/bin/python

import argparse

argparser = argparse.ArgumentParser()
argparser.add_argument("usertext",help="text to translate")
args=argparser.parse_args()
usertext = args.usertext
print(f"usertext was {usertext}")

$