Generates the key data corresponding to the given nonce

def generate_key_data_from_nonce(server_nonce, new_nonce):
    """Generates the key data corresponding to the given nonce"""
    server_nonce = server_nonce.to_bytes(16, 'little', signed=True)
    new_nonce = new_nonce.to_bytes(32, 'little', signed=True)
    hash1 = sha1(new_nonce + server_nonce).digest()
    hash2 = sha1(server_nonce + new_nonce).digest()
    hash3 = sha1(new_nonce + new_nonce).digest()

    key = hash1 + hash2[:12]
    iv = hash2[12:20] + hash3 + new_nonce[:4]
    return key, iv