Embeded the xxxdh, which iplementation of the Extended Triple Diffie-Hellman key exchange protocol written in Rust, on Python. xxxdh is written by Olexander Yermakov.
Implementation is close to the Signal Spec, but Ristretto point Curve25519 used as a curve for the default implementation. Though underlying algorithms could be changed fairly easily.
//! Basic example.
from rust_x3dh import x3dh_ser
u1_shared_secret_key, u2_shared_secret_key = x3dh_ser.gen_3xdh_secrets_key_pairs()
print(f"[u1_shared_secret_key]:{u1_shared_secret_key}")
print(f"[u2_shared_secret_key]:{u2_shared_secret_key}")