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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

Flat json to nested json python

I want to convert input json to nested json defined, I am not able to think of any json library which help me achieve this
Input json
[{'Name': 'John', 'state': 'Boston', 'currency': 'USD', 'marks': 100},
{'Name': 'Rohan', 'state': 'Paris', 'currency': 'EUR', 'marks': 20},
{'Name': 'Rohan', 'state': 'Lyon', 'currency': 'EUR', 'marks': 11.4},
{'Name': 'Messi', 'state': 'Madrid', 'currency': 'EUR', 'marks': 9.9},
{'Name': 'Lampard', 'state': 'London', 'currency': 'GBP', 'marks': 12.2},
{'Name': 'Lampard', 'state': 'London', 'currency': 'FBP', 'marks': 10.9}]
output json
{
"USD": {
"John": {
"Boston": [
{
"Marks": 100
}
]
},
Current scenario based on value Currency,Name,state,marks
The nested json can be put upto n level if required such as Name and state and marks or it can be Name , curreny , state and marks or Name,curreny and marks

So you want currency > name > state > list of marks.
One solution would be to create the structure using defaultdicts, and then just add to it.
from collections import defaultdict
from functools import wraps
data = [...]
def ddmaker(type_):
#wraps(dict)
def caller():
return defaultdict(type_)
return caller
# create the structure of the output
output = defaultdict(ddmaker(ddmaker(list)))
# add to it
for item in data:
currency = item["currency"]
name = item["Name"]
state = item["state"]
mark = item["marks"]
output[currency][name][state].append({'Marks': mark})

Retrieve only certain keys and values from a dictionary, nested inside a list

I've been stuck on this for hours.. I want to retrieve only ONE individuals keys and values from a dictionary that is nested inside of a list.
GAMERS = [{
'name': 'Fatboi',
'parent': 'Dick Van Dyke',
'game': 'Dark Souls 3',
'weight': '420 lbs'
},
{
'name': 'Justin',
'parent': 'Heather Blueberry',
'game': 'Tetris',
'weight': '180 lbs'
},
{
'name': 'jerkhead',
'parent': 'none',
'games': 'Hello Kitty',
'weight': '240 lbs'
},{
'name': 'Tumor',
'parent': 'Jack Black',
'games': 'Trying to live',
'weight': '150 lbs'
}]
So for instance I want to get Justins information printed only, nobody elses. Any insights?

You can pass the key which you want and push it to separate list.
GAMERS = [{
'name': 'Fatboi',
'parent': 'Dick Van Dyke',
'game': 'Dark Souls 3',
'weight': '420 lbs'
},
{
'name': 'Justin',
'parent': 'Heather Blueberry',
'game': 'Tetris',
'weight': '180 lbs'
},{
'name': 'jerkhead',
'parent': 'none',
'games': 'Hello Kitty',
'weight': '240 lbs'
}]
def get_key_pair_list(input_dict, key):
new_list = []
for item in input_dict:
my_dict = {}
if key in item.keys():
my_dict[key] = item[key]
new_list.append(my_dict)
return new_list
print(get_key_pair_list(GAMERS, 'name'))
Output:
[{'name': 'Fatboi'}, {'name': 'Justin'}, {'name': 'jerkhead'}]
Comprehensive way:
key = 'name'
my_list = [{key, item[key]} for item in GAMERS if key in item.keys() ]
print(my_list)
output:
[{'name', 'Fatboi'}, {'name', 'Justin'}, {'name', 'jerkhead'}]

You want to filter the list and grab the first value that matches a predicate. Make sure to handle the case where the item doesnt exist!
filtered_info = (
item for item in GAMERS if item['name'] == 'Justin'
)
justin_info = next(filtered_info, None)
if justin_info is not None:
print(justin_info)

pystache: render context inside lambda

This is very similar to https://github.com/defunkt/pystache/issues/157, however in the mentioned post didn't really answer...
My target: print the following lines:
Al,John,Jack
Tim,Tom,Todd
without a final comma.
I tried this way:
ctx = {
'gangs': [
{'gangsters': [ {'name': 'Al' }, {'name': 'John'}, {'name': 'Jack'}]},
{'gangsters': [ {'name': 'Tim'}, {'name': 'Tom'} , {'name': 'Todd'}]},
]
}
class Lambdas(object):
def __init__(self, renderer):
self.renderer = renderer
def rstrip(self):
"Remove last character"
print self.renderer.context
return lambda s: self.renderer.render(s, self.renderer.context)[:-1]
renderer = pystache.Renderer(missing_tags='strict')
print renderer.render("""
{{#gangs}}
{{#rstrip}}{{#gangsters}}{{name}},{{/gangsters}}{{/rstrip}}
{{/gangs}}
""", ctx, Lambdas(renderer))
The output:
ContextStack({'gangs': [{'gangsters': [{'name': 'Al'}, {'name': 'John'}, {'name': 'Jack'}]}, {'gangsters': [{'name': 'Tim'}, {'name': 'Tom'}, {'name': 'Todd'}]}]}, <__main__.Lambdas object at 0x15cadb10>, {'gangsters': [{'name': 'Al'}, {'name': 'John'}, {'name': 'Jack'}]})
ContextStack({'gangs': [{'gangsters': [{'name': 'Al'}, {'name': 'John'}, {'name': 'Jack'}]}, {'gangsters': [{'name': 'Tim'}, {'name': 'Tom'}, {'name': 'Todd'}]}]}, <__main__.Lambdas object at 0x15cadb10>, {'gangsters': [{'name': 'Al'}, {'name': 'John'}, {'name': 'Jack'}]})
Al,John,Jack
Al,John,Jack
The culprit is the invocation to render() inside rstrip. Notice how, during the second call, the 3d element of the ContextStack is exactly identical to the previous call.
Is this a bug, or am I missing something?!?

Answered upstream: https://github.com/defunkt/pystache/issues/158
def rstrip(self):
"Remove last character"
return lambda s: copy.deepcopy(self.renderer).render(s, self.renderer.context)[:-1]

Appending/Merging in Python

I have the following structure:
[
{
u'123456': {'name': "Bill"},
u'234567': {'name': "Dave"},
u'345678': {'name': "Tom"}
},
]
During a for loop new items are added to the list using the extend function. Unfortunately this results in the following structure:
[
{
u'123456': {'name': "Bill"},
u'234567': {'name': "Dave"},
u'345678': {'name': "Tom"}
},
{
u'555555': {'name': "Steve"},
u'666666': {'name': "Michael"},
u'777777': {'name': "George"}
}
]
The intended result is actually a flat structure such in the following:
[
{
u'123456': {'name': "Bill"},
u'234567': {'name': "Dave"},
u'345678': {'name': "Tom"},
u'555555': {'name': "Steve"},
u'666666': {'name': "Michael"},
u'777777': {'name': "George"}
}
]
Is it possible to append to the list so that the structure gets built in a flat way.
or
Is it possible to flatten after the loop has finished?

If your list is named l you could use l[0].update(new_dict).
Example:
l = [{u'123456': {'name': "Bill"}}]
l[0].update({u'234567': {'name': "Dave"}})
print(l)
Nice formatted output is:
[
{
u'123456': {'name': 'Bill'},
u'234567': {'name': 'Dave'}
}
]

Where you currently have something like this:
mylist.extend(newdict)
You should use this:
mylist[0].update(newdict)

You can add the items of both dictionaries together:
>>> mylist = [
{
u'123456': {'name': "Bill"},
u'234567': {'name': "Dave"},
u'345678': {'name': "Tom"}
},
]
>>> mydict = {
u'555555': {'name': "Steve"},
u'666666': {'name': "Michael"},
u'777777': {'name': "George"}
}
>>> [dict(mylist[0].items() + mydict.items())]
[{u'123456': {'name': 'Bill'}, u'555555': {'name': 'Steve'}, u'777777': {'name': 'George'}, u'666666': {'name': 'Michael'}, u'345678': {'name': 'Tom'}, u'234567': {'name': 'Dave'}}]
Although it's more clean to just do .update():
>>> mylist[0].update(mydict)

You can use .update(), however this will overwrite values if you'll have duplicated keys.
def flatten(results):
newresult = {}
for subdict : results:
newresult.update(subdict)
return [newresult]