[Python] Cisco IOU License invalid for GNS3

I am using GNS3 on VMWare Fusion to create Cisco topology with L2 and L3 devices. I am unable to start the devices. I keep getting the error that the IOU license is invalid. Used this Python script to create the license:

#!/usr/bin/env python3
import socket
import hashlib
import struct

print("*********************************************************************")
print("Cisco IOU License Generator - Kal 2011, python port of 2006 C version")
print("Modified to work with python3 by c_d 2014")

# Use a manual hostid value, or generate one based on hostname
hostname = "gns3vm"
hostid = "hostid" # replaces with the hostid of my VM
ioukey = int(hostid, 16)

for x in hostname:
ioukey += ord(x)

print(f"hostid={hostid}, hostname={hostname}, ioukey={hex(ioukey)[2:]}")

iouPad1 = b'\x4B\x58\x21\x81\x56\x7B\x0D\xF3\x21\x43\x9B\x7E\xAC\x1D\xE6\x8A'
iouPad2 = b'\x80' * 32

# Fix: use '!I' to support unsigned int
md5input = iouPad1 + iouPad2 + struct.pack('!I', ioukey) + iouPad1
iouLicense = hashlib.md5(md5input).hexdigest()[:16]

print("\nAdd the following text to ~/.iourc:")
print(f"[license]")
print(f"{hostname} = {iouLicense};")


Got the result of this code as:

[license]
gns3vm = xxxxxxxxxxxxxxxx; # instead of x I have the license


Uploaded it to the GNS3 but it says invalid.

What Am I doing wrong?

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