How to remove duplicates from email G Suite?

Hi everyone,
I’m working with a list of email addresses and noticed that some of them appear more than once. I’d like to clean up the list by removing any duplicates so that each email shows up only once.
The list might be in different formats, such as a .txt file or Excel sheet, or stored in a database.
What’s the best way to remove duplicates in this case? Any help or suggestions would be appreciated!
Thanks!