possible pairings in a set

[Ross]

I'm new to python and I'm trying to come up with a function that takes
a given number of players in a game and returns all possible unique
pairings. Here's the code I've come up with so far, but I'm not
getting the output I'd like to:

def all_pairings(players):
	cleanlist = []
	for i in range(players):
		cleanlist.append(i)
	return cleanlist
	start = 0
	follow = start +1
	finallist = []
	while follow <= len(cleanlist)-1:
		for player in cleanlist:
			mini = cleanlist[start],cleanlist[follow]
			finallist.append(mini)
			follow +=1
		start+=1
	return finallist

If I were to execute the function with all_pairings(4), I want to get
the output [[0,1],[0,2],[0,3],[1,2],[1,3],[2,3]. Instead, I get
[0,1,2,3] with the code I currently have. Can you guys help me out?
Also, if my code is considered ugly or redundant by this community,
can you make suggestions to clean it up?