How to write a nested dict with lists as values for each nested dict

Question

I think I know what I want. My output needs to have "teams" as dict keys, for each dict key there will be a nested dict, in each nested dict the key will be a players name, the values for each nested dict key will be a list of goals per game. I want to be able to find out who scored the highest amount of goals for each team eventually.

I don't know if a dataframe is better for this?

code to make nested dict - I didn't know how to do it

mydict = {"team" : {"players" : "goals_each_game"}}

team = list(range(1, 7))
print("team : ", team)
players = ["gk", "lb", "dl", "dr", "rb", "rw", "rm", "lm", "lw", "ls", "rs" ]
goals_each_game = list(range(1,7))

for d in team:
    for k, v in mydict.items():
        mydict["team"] = d
        


        #mydict[v] = a nested dict of each player and their list of goals
        for p in players:

            teamlist = []

            new_dict = {}

            for k,v in new_dict.items():

                new_dict[k] = p

                new_dict[v] = goals_each_game

                teamlist.append(new_dict)


        mydict[v] = teamlist


            

for k,v in mydict.items():
    print(k,v)

expected output

I want to know how to make this, and put any list of values inside the nested dicts instead of [1, 2, 3].

mydict = {"1": [{"gk":[1,2,3]}, {"lb":[1,2,3]}] ,"2": [{"gk":[1,2,3]}, {"lb":[1,2,3]}], "3": [{"gk":[1,2,3]}, {"lb":[1,2,3]}] ,"4": [{"gk":[1,2,3]}, {"lb":[1,2,3]}] }


for k,v in mydict.items():
    print(k,v)

team :  [1, 2, 3, 4, 5, 6]
1 [{'gk': [1, 2, 3]}, {'lb': [1, 2, 3]}]
2 [{'gk': [1, 2, 3]}, {'lb': [1, 2, 3]}]
3 [{'gk': [1, 2, 3]}, {'lb': [1, 2, 3]}]
4 [{'gk': [1, 2, 3]}, {'lb': [1, 2, 3]}]

Answer 1

Your outer-most dictionary is a dictionary whose keys are team indices and whose values are lists .

If your goal's to have each value be a dictionary of player initials to goals scored, you want teamlist to be a {} (and the call to teamlist.append to be replaced with an assignment).

You could write this more idiomatically with a comprehension:

goals_per_game = list(range(1, 7))

mapping = {
    d: {
        p: goals_per_game
        for p in players
    }
    for d in teams
}

There's a few caveats here. The first is that all teams share the same players; you may want to maintain a separate dictionary mapping teams to player initials.

The second is that—as written— goals_per_game will be the same object across all players:

Assignment statements in Python do not copy objects, they create bindings between a target and an object

(reference)

This means that mutating the list for one player will mutate it for all players in the above implementation. Consider:

mapping[1]['gk'].append(100)

print(mapping[2]['lb'])  # Has 100!

To address this, you can either construct a new list for each player (ie by calling list o range separately) or use copy to construct a copy for each player.