How to use the fastecdsa.point.Point function in fastecdsa

def pub_key_to_point(pub_key: str) -> Point:
    '''
    Given a public key, return a Point object
    (Used to verify signatures)
    '''
    xs, ys = pub_key.split('x')
    return Point(int(xs, 16), int(ys, 16), curve=curve.P256)

:return HDKey: HD Key class object
        """
        if network is None:
            network = self.network.name
        if index > 0x80000000:
            raise BKeyError("Cannot derive hardened key from public private key. Index must be less than 0x80000000")
        data = self.public_byte + struct.pack('>L', index)
        key, chain = self._key_derivation(data)
        key = change_base(key, 256, 10)
        if key >= secp256k1_n:
            raise BKeyError("Key cannot be greater than secp256k1_n. Try another index number.")

        x, y = self.public_point()
        if USE_FASTECDSA:
            ki = ec_point(key) + fastecdsa_point.Point(x, y, fastecdsa_secp256k1)
            ki_x = ki.x
            ki_y = ki.y
        else:
            ki = ec_point(key) + ecdsa.ellipticcurve.Point(secp256k1_curve, x, y, secp256k1_n)
            ki_x = ki.x()
            ki_y = ki.y()

        if ki_y % 2:
            prefix = '03'
        else:
            prefix = '02'
        xhex = change_base(ki_x, 10, 16, 64)
        secret = binascii.unhexlify(prefix + xhex)
        return HDKey(key=secret, chain=chain, depth=self.depth+1, parent_fingerprint=self.fingerprint,
                     child_index=index, is_private=False, witness_type=self.witness_type, multisig=self.multisig,
                     encoding=self.encoding, network=network)

x = int.from_bytes(pub_key[1:], "big")

            y_y = pow(x, 3) + CURVE.a * x + CURVE.b
            y = mod_sqrt(y_y, CURVE.p, y_odd)

        elif len(pub_key) == 65:
            tag = pub_key[0:1]
            assert tag == SECP256K1_TAG_PUBKEY_UNCOMPRESSED

            x = int.from_bytes(pub_key[1:ENCODED_SIZE + 1], "big")
            y = int.from_bytes(pub_key[ENCODED_SIZE + 1:], "big")

        else:
            raise NotImplementedError

        return point.Point(x, y, CURVE)
    except:
        raise ValueError("The public key could not be parsed or is invalid")