I am designing a web application that has users becoming friends with other users. I am storing the users info in a database using sqlite3. 
I am brainstorming on how I can keep track on who is friends with whom.
What I am thinking so far is; to make a column in my database called Friendships where I store the various user_ids( integers) from the user's friends.
I would have to store multiple integers in one column...how would I do that?
Is it possible to store a python list in a column?
I am also open to other ideas on how to store the friendship network information in my database....
The application runs through FLASK
It is possible to store a list as a string into an sql column.  
However, you should instead be looking at creating a Friendships table with primary keys being the user and the friend.
So that you can call the friendships table to pull up the list of friends.
Otherwise, I would suggest looking into a Graph Database, which handles this kind of things well too.
Storing multiple values in one column