Case Sensitivity

[deivisk]

Hello, this is my first post. I'm a complete newbie in coding and I ran into a brick wall. I need to make the comparison between two lists case insensitive and no idea how to incorporate it into the code. I know it has to do something with .lower() but no idea how. I would appreciate the help. Thanks

current_users=['sandra', 'brigita', 'bri','deivis', 'raimis']
new_users=['bri', 'billy', 'minde', 'erika', 'edminrika', 'RAIMIS']
for new_user in new_users:
    if new_user in current_users:
        print(new_user+" "+"already exists."+" "+"You need to choose a different name.\n")
    else:
        print(new_user+" "+"is available.")