System
Public Key

# Python (cryptography library)
from cryptography.hazmat.primitives.asymmetric.ed25519 import Ed25519PublicKey
import binascii, json, hashlib

pub_hex = "PUBLIC_KEY_HEX"
pub_key = Ed25519PublicKey.from_public_bytes(bytes.fromhex(pub_hex))

cert = json.load(open("certificate.json"))
sig  = cert.pop("signature")
cert.pop("certificate_hash", None)
# RFC-8785 canonical JSON (key-sorted)
canonical = json.dumps(cert, sort_keys=True, separators=(',',':'))
pub_key.verify(bytes.fromhex(sig), canonical.encode())