I’d have two advices for you:
1) Use ArrayField if you are using PostgreSQL as your database. You can read more about ArrayField here.
2) Encode your array as JSON and store it either as a plain string or using a JSONField as found here.
I’d personally prefer option number 1 since that is the cleaner and nicer way but depending on what you are actually using to store your data that might not be available to you.