rsa_encrypt

[PhS]

Hello

I would like to crypt data with public key to be send to a server with my lopy.
When, i read the official documentation
and test the example: the rsa_encrypt function is missing !

The function rsa_decypt is missing too.

Traceback (most recent call last):
  File "<stdin>", line 13, in <module>
AttributeError: 'module' object has no attribute 'rsa_encrypt'
>
Pycom MicroPython 1.20.0.rc13 [v1.9.4-94bb382] on 2019-08-22; LoPy with ESP32
Type "help()" for more information.

Here my code

# send data to a server
import crypto

payload = "this is a secret message, it needs to be encrypted"

# read the key from file
f = open("cert/public_serveur.pem")
pk = f.read()
f.close()

# Encrypt the message
message_encrypted = crypto.rsa_encrypt(payload, pk)

If You have a solution ..
Thank's