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How to reverse a dict [closed]

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As I understand, a dict has every key unique; if you put two identical key in a dict the first key will be overwritten by the second like this example
my_dict = {
'name': 'John',
'age': 30,
'city': 'New York',
'age': 40
}
print(my_dict)
The result will be
{'name': 'John', 'age': 40, 'city': 'New York'}
How can I manage to do so the second will be overwritten by the first like this example?
my_dict = {
'name': 'John',
'age': 30,
'city': 'New York',
'age': 40
}
print(my_dict)
I want the result to be
{'name': 'John', 'age': 30, 'city': 'New York'}
I tried functions but the dict already does that by default. So no point on doing a function.

Comprehension list of nested dictionary to get values but got keys

Fairly new to list comprehension and have the_list that I want to extract the keys of nested dictionary but I got the values instead. What am I missing or what am I doing wrong?
the_list = [{'size': 0, 'values': [], 'start': 0}, {'size': 2, 'values': [{'user': {'name': 'anna', 'id': 10, 'displayName': 'Anna'}, 'category': 'Secretary'}, {'user': {'name': 'bob', 'id': 11, 'displayName': 'Bobby'}, 'category': 'Manager'}], 'start': 0}, {'size': 1, 'values': [{'user': {'name': 'claire', 'id': 13, 'displayName': 'Clarissa Claire'}, 'category': 'Secretary'}], 'start': 0}]
list_comprehension = []
list_comprehension = [x for x in the_list for x in the_list[1]['values'][0]]
print(list_comprehension)
>> ['user', 'category', 'user', 'category', 'user', 'category']
Want
list_comprehension = [[anna, Secretary], [bob, manager], [claire, Secretary]]

You could use this. I personnally try to avoid nested list comprehension as they are hard to read and debug.
[[x['category'], x['user']['displayName']] for nest_list in the_list for x in nest_list["values"] ]
Output:
[['Secretary', 'Anna'], ['Manager', 'Bobby'], ['Secretary', 'Clarissa Claire']]
EDIT:
A version that doesn't have a nested comprehension list. When doing it I realised that there was one more level than I realised that makes this version a bit long. So in the end I'm not sure which one I would use in prod.
result = []
dict_list = [nest_list["values"] for nest_list in the_list]
for elt in dict_list:
for d in elt:
result.append([d['category'], d['user']['displayName']])

I've come up with this solution, but it is not very readable ...
comprehensionList = [[user['user']['name'], user['category']] for x in the_list for user in x['values']]
# Output
[['anna', 'Secretary'], ['bob', 'Manager'], ['claire', 'Secretary']]

Python dictionary to multiple list [closed]

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The current problem consists of the conversion of a dictionary to a list. I am unable to split the specific value of key and value pair into my desired results.
I have a dictionary that looks like this:
dict = [ {name:aa,age:12, id:121}, {name:bb,age:13, id:122},{name:cc,age:11, id:121}, {name:dd,age:15, id:122} ]
It has certain pairs of key and values and the 'ID' key is the most important of them.the ID value is repeated and so I am looking for lists of that value such that it would looks like this:
121 = [
{name:aa,age:12},
{name:cc,age:11}
]
122 = [
{name:bb,age:13},
{name:dd,age:15}
]

I think this should work fine, just looping through the list of sub-dictionaries.
start_dict = [{'name':'aa','age':12,'id':121}, {'name':'bb','age':13,'id':122},{'name':'cc','age':11,'id':121}, {'name':'dd','age':15,'id':122}]
converted_dict = {}
for subdict in start_dict:
if subdict['id'] not in converted_dict:
converted_dict[subdict['id']] = [{k:v for k,v in subdict.items() if k != 'id'}]
else:
converted_dict[subdict['id']].append({k:v for k,v in subdict.items() if k != 'id'})
print(converted_dict)
{121: [{'name': 'aa', 'age': 12}, {'name': 'cc', 'age': 11}],
122: [{'name': 'bb', 'age': 13}, {'name': 'dd', 'age': 15}]}

from collections import defaultdict
start_dict = [
{'name': 'aa', 'age': 12, 'id': 121},
{'name': 'bb', 'age': 13, 'id': 122},
{'name': 'cc', 'age': 11, 'id': 121},
{'name': 'dd', 'age': 15, 'id': 122},
]
new_dict = defaultdict(list)
for entry in start_dict:
new_dict[entry["id"]].append(dict(name=entry["name"], age=entry["age"]))
print(dict(new_dict))

Python dicts in a list, show highest score groupped by dictkey [closed]

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I'm struggling to get the result from the following code:
list_result = [{'name':'John', 'score':5}, {'name':'John', 'score':6}, {'name':'James', 'score':7}, {'name':'James', 'score':8}]
My expected result is to group them by highest score (to show highest score per user), how do I do that?
Expected Result:
[{'name': 'John', 'score': 6}, {'name': 'James', 'score': 8}]

Here's a way to do it with an ordered dictionary, without pandas:
list_result = [{'name':'John', 'score':5}, {'name':'John', 'score':6}, {'name':'James', 'score':7}, {'name':'James', 'score':8}]
ord_dict = collections.OrderedDict()
for i in sorted(list_result, key=lambda x: x["score"]):
ord_dict[i["name"]] = i["score"]
print([{"name":k, "score":v} for k,v in ord_dict.items()])
The output is:
[{'name': 'John', 'score': 6}, {'name': 'James', 'score': 8}]

You can use pandas.DataFrame and its groupby() method like this:
>>> import pandas as pd
>>> df = pd.DataFrame(list_result)
>>> df.groupby('name').score.max().reset_index().to_dict(orient='records')
[{'name': 'James', 'score': 8}, {'name': 'John', 'score': 6}]

import collections
import math
list_result = [
{'name':'John', 'score': 5},
{'name':'John', 'score': 6},
{'name':'James', 'score': 7},
{'name':'James', 'score': 8}
]
max_score_by_user = collections.defaultdict(lambda: -math.inf)
for result in list_result:
name, score = result['name'], result['score']
max_score_by_user[name] = max(max_score_by_user[name], score)
print(*max_score_by_user.items(), sep='\n')
Which prints:
('John', 6)
('James', 8)

You can try:
list_result = [{'name':'John', 'score':5}, {'name':'John', 'score':6}, {'name':'James', 'score':7}, {'name':'James', 'score':8}]
output_dict = {}
for result in list_result:
if result["name"] in output_dict:
if result["score"] > output_dict[result["name"]]:
output_dict[result["name"]] = result["score"]
else:
output_dict[result["name"]] = result["score"]
output_list = []
for output_key, output_val in output_dict.items():
output_list.append({"name": output_key, "score": output_val})
print(output_list)
Output:
[{'name': 'John', 'score': 6}, {'name': 'James', 'score': 8}]

my_dict = {'x':500, 'y':5874, 'z': 560}
key_max = max(my_dict.keys(), key=(lambda k: my_dict[k]))
key_min = min(my_dict.keys(), key=(lambda k: my_dict[k]))
print('Maximum Value: ',my_dict[key_max])
print('Minimum Value: ',my_dict[key_min])
Copy
Sample Output:
Maximum Value: 5874
Minimum Value: 500

How can i insert a list of dictionaries into my existing item

I want to insert something in Python 3.8 with Pymongo
I got a short question. I have a list of dictionaries called items:
item_list = [{'name': 'abc', 'category': 'cde', 'assurance': 0.9844486508518457, 'count': 1},
{'name': 'abc', 'category': 'cde', 'assurance': 0.7428154349327087, 'count': 1},
{'name': 'abc', 'category': 'cde', 'assurance': 0.9954652488231659, 'count': 1}]
I also have my database item:
item = collection.find_one(<placeholder>)
Now I tried the following:
collection.update_one(item, {"$set": {"Entity": item_list} }, True)
But this does not work... How can I insert a list of dictionaries?
Thank you.