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python according to the same value combining dictionary

i have a list of dict like this
[
{'id': 'A123',
'feature': {'name': 'jack', 'age' : '18' },
'create_time': '2022-5-17 10:29:47',
'is_fast': False},
{'id': 'A123',
'feature': {'gender': 'male'},
'create_time': '2022-5-17 10:29:47',
'is_fast': False},
{'id': 'A123',
'habit': {'name': 'read'},
'create_time': '2022-5-15 10:29:45',
'is_fast': False},
{'id': 'A456',
'feature': {'name': 'rose'},
'create_time': '2022-4-15 10:29:45',
'is_fast': False},
{'id': 'A456',
'habit': {'name': 'sport'},
'create_time': '2022-3-15 10:29:45',
'is_fast': False}
]
But I want to merge the same "id" values ​​together using something function
The desired output is as follows
[
{'id': 'A123',
'feature': {'name': 'jack', 'age' : '18' ,'gender': 'male'},
'habit': {'name': 'read'},
'create_time': '2022-5-19 10:29:47', #Get the latest time based on the same id
'is_fast': False},
{'id': 'A456',
'feature': {'name': 'rose'},
'habit': {'name': 'sport'},
'create_time': '2022-4-15 10:29:45',
'is_fast': False},
]
How can I merge the same "id" values ​​according to these dictionaries..

This should get you started... I put some inline notes to explain what the code is doing. You still need to implement a date time comparison.
def merge_dicts(lst):
final = {} # results
for row in lst: # iterate through list
if row['id'] not in final: # if current item id hasnt been seen
final[row['id']] = row # assign it to results with id as the key
else:
record = final[row['id']] # otherwise compare to data already stored
for k,v in row.items(): #iterate through dictionary items
if k not in record: # if key not in results
record[k] = v # add the key and value
continue
if record[k] == v: continue # if they are already equal move on
if isinstance(v, dict): # if its a dictionary
record[k].update(v) # update the dictionary
else: # must be date time sequence so do some datetime comparison
"""Do some date comparison and assign correct date"""
return [v for k,v in final.items()] # convert to list
print(merge_dicts(lst))
output:
[
{
'id': 'A123',
'feature': {'name': 'jack', 'age': '18', 'gender': 'male'},
'create_time': '2022-5-17 10:29:47',
'is_fast': False,
'habit': {'name': 'read'}
},
{
'id': 'A456',
'feature': {'name': 'rose'},
'create_time': '2022-4-15 10:29:45',
'is_fast': False,
'habit': {'name': 'sport'}
}
]

You can use the dict.setdefault method to initialize sub-dicts under keys that don't already exist to avoid cluttering up your code with conditional statements that test the existence of keys:
merged = {}
for d in lst:
s = merged.setdefault(d['id'], d)
for k, v in d.items():
if isinstance(v, dict):
s.setdefault(k, v).update(v)
elif v > s[k]: # the dates/times in the input follow alphabetical order
s[k] = v # later dates/times takes precedence
print(list(merged.values()))
Demo: https://replit.com/#blhsing/BlandCarelessPolygons#main.py

Recursive dictionary searching

I'm trying to make a function that would take nested array (dict/list in any order) and a key name as arguments and return all values of that key in a list.
my_key = "Items"
my_dict = [{'z': 0, 'x': 0, 'y': 0, 'Items': [{'Slot': 1, 'id': 'minecraft:rail', 'Count': 1}, {'Slot': 2, 'id': 'minecraft:white_shulker_box', 'tag': {'BlockEntityTag': {'id': 'minecraft:shulker_box', 'Items': [{'Slot': 0, 'Count': 1, 'tag': {'Items': [{'id': 'minecraft:amethyst_shard', 'Count': 1}]}, 'id': 'minecraft:bundle'}]}}, 'Count': 1}]}]
def recursive_lookup(data, key):
if isinstance(data, list):
for i in data:
recursive_lookup(i, key)
elif isinstance(data, dict):
for i, v in data.items():
if i == key:
print(f'{v = }')
if isinstance(v, list) or isinstance(v, dict): recursive_lookup(v, key)
print(recursive_lookup(my_dict, my_key))
Currently it prints out found items at print(f'{v = }'). How can I store those in a list and pass as a function return?

You can use .extend() to concatenate the result of recursive calls to a list.
def recursive_lookup(data, key):
values = []
if isinstance(data, list):
for i in data:
values.extend(recursive_lookup(i, key))
elif isinstance(data, dict):
for i, v in data.items():
if i == key:
values.append(v)
if isinstance(v, list) or isinstance(v, dict):
values.extend(recursive_lookup(v, key))
return values

You can what you want without any explicit recursion at all by making use of the json module in the standard library (assuming your data can be serialized into that format). This is because the JSON decoder supports an object_hook argument which is a function it will call everytime it encounters a dictionary.
The basic idea is to specify a function via this argument that merely "watches" what is being decoded and checks it for the sought-after key.
Here's what I mean:
import json
my_key = "Items"
my_dict = [{'z': 0, 'x': 0, 'y': 0, 'Items': [{'Slot': 1, 'id': 'minecraft:rail', 'Count': 1}, {'Slot': 2, 'id': 'minecraft:white_shulker_box', 'tag': {'BlockEntityTag': {'id': 'minecraft:shulker_box', 'Items': [{'Slot': 0, 'Count': 1, 'tag': {'Items': [{'id': 'minecraft:amethyst_shard', 'Count': 1}]}, 'id': 'minecraft:bundle'}]}}, 'Count': 1}]}]
def lookup(data, key):
results = []
def decode_dict(a_dict):
try:
results.append(a_dict[key])
except KeyError:
pass
return a_dict
json_repr = json.dumps(data) # Convert to JSON format.
json.loads(json_repr, object_hook=decode_dict) # Return value ignored.
return results
from pprint import pprint
pprint(lookup(my_dict, my_key), sort_dicts=False)
Pretty-printed result list:
[[{'id': 'minecraft:amethyst_shard', 'Count': 1}],
[{'Slot': 0,
'Count': 1,
'tag': {'Items': [{'id': 'minecraft:amethyst_shard', 'Count': 1}]},
'id': 'minecraft:bundle'}],
[{'Slot': 1, 'id': 'minecraft:rail', 'Count': 1},
{'Slot': 2,
'id': 'minecraft:white_shulker_box',
'tag': {'BlockEntityTag': {'id': 'minecraft:shulker_box',
'Items': [{'Slot': 0,
'Count': 1,
'tag': {'Items': [{'id': 'minecraft:amethyst_shard',
'Count': 1}]},
'id': 'minecraft:bundle'}]}},
'Count': 1}]]

You can keep a running list:
def recursive_lookup(data, key):
lst = []
if isinstance(data, list):
for i in data:
lst.append(recursive_lookup(i, key))
elif isinstance(data, dict):
for i, v in data.items():
if i == key:
lst.append([v])
if isinstance(v, list) or isinstance(v, dict): lst.append(recursive_lookup(v, key))
return lst
print(recursive_lookup(data, 'Items'))

Update a list of Dict based on another Dict

I have a dict as follows.
dict = {'P': ['Demo'], 'Q': ['PMS']}
And I have a list of Dict as follows.
all = [{'Name': 'PMS'}, {'Name': 'Demo'}]
I need to have the dict's respective value in all as bellow.
new_list = [{'Name': 'PMS','Code': 'Q'}, {'Name': 'Demo','Code': 'P'}]

In this specific case, given that the values are just strings and therefore hashable objects, you can use a dictionary of reverse mappings. Be aware that it could not be used if the values were not hashable.
dct = {'P': ['Demo'], 'Q': ['PMS']}
all = [{'Name': 'PMS'}, {'Name': 'Demo'}]
reverse_mapping = {v[0]:k for k, v in dct.items()}
new_list = [d.copy() for d in all]
for d in new_list:
d['Code'] = reverse_mapping[d['Name']]
print(new_list)
This gives:
[{'Name': 'PMS', 'Code': 'Q'}, {'Name': 'Demo', 'Code': 'P'}]

dct = {'P': ['Demo'], 'Q': ['PMS']}
all_ = [{'Name': 'PMS'}, {'Name': 'Demo'}]
out = [dict(**l, Code=next(k for k, v in dct.items() if l['Name'] in v)) for l in all_]
print(out)
Prints:
[{'Name': 'PMS', 'Code': 'Q'}, {'Name': 'Demo', 'Code': 'P'}]
Or: you can make temporary dictionary:
tmp = {v[0]:k for k, v in dct.items()}
out = [dict(**l, Code=tmp[l['Name']]) for l in all_]
print(out)

You could make an inverted dictionary of codes, then go through the list of dictionaries and add the codes in:
codes = {"P": ["Demo"], "Q": ["PMS"]}
lst = [{"Name": "PMS"}, {"Name": "Demo"}]
inverted_codes = {value: key for key, values in codes.items() for value in values}
# {'Demo': 'P', 'PMS': 'Q'}
for dic in lst:
code = dic["Name"]
dic["Code"] = inverted_codes[code]
print(lst)
Output
[{'Name': 'PMS', 'Code': 'Q'}, {'Name': 'Demo', 'Code': 'P'}]

how to create a new key from a value of another key Python

I have a list of dictionaries that looks like the following:
data = [{'Name': 'Paul', 'Date': '20200412', 'ID': '1020'}, {'Name': 'Frank', 'Date': '20200413', 'ID': '1030'}, {'Name': 'Anna', 'Date': '20200414', 'ID': '1040'}]
I need to create a new list of dictionaries, where ID's value would be the key, and the value is another dictionary with key/values associated with this specific ID.
This is the desired output:
new_data = [{'1020': {'Name': 'Paul', 'Date': '20200412'}},
{'1030': {'Name': 'Frank', 'Date': '20200413'}},
{'1040': {'Name': 'Anna', 'Date': '20200414'}}]
I have tried:
for index, my_dict in enumerate(data):
new_data = []
key = my_dict['ID']
new_data.append(key)
But that only assigned the key value, not sure how to push it into into a new dict along with other key/values.

>>> [{i['ID']: {k:v for k,v in i.items() if k != 'ID'}} for i in data]
[{'1020': {'Name': 'Paul', 'Date': '20200412'}},
{'1030': {'Name': 'Frank', 'Date': '20200413'}},
{'1040': {'Name': 'Anna', 'Date': '20200414'}}]

new_data = []
for index, my_dict in enumerate(data):
key = my_dict['ID']
del my_dict['ID']
new_data.append({key:data[index]})

To add the other values you simply need to create a new dict like this:
new_data.append( key:{
'name':my_dict['name']
'Date':my_dict['date']
}
You also don't need to make the 'key' variable, you can just use 'my_dict['ID']'

You could try this list comprehension:
[{x["ID"]: {k: v for k, v in x.items() if k != "ID"}} for x in data]
Which assigns ID as the parent key to the dictionary, and filters out the ID key from the child dictionary inside a dict comprehension
Which could be broken down into this:
result = []
for x in data:
result.append({x["ID"]: {k: v for k, v in x.items() if k != "ID"}})
And even to a straightforward loop approach:
result = []
for x in data:
dic = {x["ID"]: {}}
for k, v in x.items():
if k != "ID":
dic[x["ID"]][k] = v
result.append(dic)
Output:
[{'1020': {'Name': 'Paul', 'Date': '20200412'}}, {'1030': {'Name': 'Frank', 'Date': '20200413'}}, {'1040': {'Name': 'Anna', 'Date': '20200414'}}]

How to change values in a nested dictionary

I need to change values in a nested dictionary. Consider this dictionary:
stocks = {
'name': 'stocks',
'IBM': 146.48,
'MSFT': 44.11,
'CSCO': 25.54,
'micro': {'name': 'micro', 'age': 1}
}
I need to loop through all the keys and change the values of all the name keys.
stocks.name
stocks.micro.name
These keys need to be changed. But, I will not know which keys to change before hand. So, I'll need to loop through keys and change the values.
Example
change_keys("name", "test")
Output
{
'name': 'test',
'IBM': 146.48,
'MSFT': 44.11,
'CSCO': 25.54,
'micro': {'name': 'test', 'age': 1}
}

A recursive solution that supports unknown number of nesting levels:
def change_key(d, required_key, new_value):
for k, v in d.items():
if isinstance(v, dict):
change_key(v, required_key, new_value)
if k == required_key:
d[k] = new_value
stocks = {
'name': 'stocks',
'IBM': 146.48,
'MSFT': 44.11,
'CSCO': 25.54,
'micro': {'name': 'micro', 'age': 1}
}
change_key(stocks, 'name', 'new_value')
print(stocks)
# {'name': 'new_value',
# 'MSFT': 44.11,
# 'CSCO': 25.54,
# 'IBM': 146.48,
# 'micro': {'name': 'new_value',
# 'age': 1}
# }

def changeKeys(d, repl):
for k,v in zip(d.keys(),d.values()):
if isinstance(v, dict):
changeKeys(v,repl)
elif k == "name":
d[k]= repl