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How edit python dict in example?

I have a dict:
my_dict = {'some.key' : 'value'}
and i want to change it like this:
result = {'some' : {'key' : 'value'}}
how i can do this?
I need to this to create nested classes using dicts:
example:
my_dict = {'nested.key' : 'value'}
class Nested:
key : str
class MyDict:
nested : Nested

if you need this for real use, and not as a coding exercise, you can install extradict and use extradict.NestedData:
In [1]: from extradict import NestedData
In [2]: a = NestedData({'some.key' : 'value'})
In [3]: a["some"]
Out[3]: {'key': <str>}
In [4]: a["some"]["key"]
Out[4]: 'value'
In [5]: a.data
Out[5]: {'some': {'key': 'value'}}
(disclaimer: I am the package author)

Not quite sure if I understand your question, but would
result = {key.split('.')[0]: {key.split('.')[1]: value} for key, value in my_dict.items()}
do the trick?

I hope this function will help you
def foo(obj):
result = {}
for k, v in obj.items():
keys = k.split('.')
caret = result
for i in range(len(keys)):
curr_key = keys[i]
if i == len(keys) - 1:
caret[curr_key] = v
else:
caret.setdefault(curr_key, {})
caret = caret[curr_key]
return result

with recurtion it could look like this (having all keys unique is essential):
my_dict = {'key0' : 'value0',
'nested.key' : 'value',
'nested1.nested1.key1' : 'value1',
'nested2.nested2.nested2.key2' : 'value2'}
def func(k,v):
if not '.' in k: return {k:v}
k1,k = k.split('.',1)
return {k1:func(k,v)}
res = {}
for k,v in my_dict.items():
res.update(func(k,v))
>>> res
'''
{'key0': 'value0',
'nested': {'key': 'value'},
'nested1': {'nested1': {'key1': 'value1'}},
'nested2': {'nested2': {'nested2': {'key2': 'value2'}}}}

Apply json patch to a Mongoengine document

I'm trying to apply a json-patch to a Mongoengine Document.
I'm using these json-patch library: https://github.com/stefankoegl/python-json-patch and mongoengine 0.14.3 with python 3.6.3
This is my actual code:
json_patch = JsonPatch.from_string(jp_string)
document = Document.objects(id=document_id)
json_documents = json.loads(document.as_pymongo().to_json())
json_patched_document = json_patch.apply(json_documents[0])
Document.objects(id=document_id).first().delete()
Document
.from_json(json.dumps(json_patched_document))
.save(force_insert=True)
Is there a better way to save an edited json document?
I've enhanced a little bit the code:
json_patch = JsonPatch.from_string(jp_string)
document = Document.objects(id=document_id)
json_document = json.loads(document.as_pymongo().to_json())
json_patched_document = json_patch.apply(json_documents[0])
Document
.from_json(json.dumps(json_patched_document), created=True)
.save()
but, is there a way to not convert the document to json?

I had slightly similar problem, the part that I dont wanted the complete Document for saving, I just wanted to update fields which are modified/added.
heres the code I tests on below inputs:
def tryjsonpatch():
doc_in_db = {'foo': 'bar', "name": "aj", 'numbers': [1, 3, 7, 8]}
input = {'foo': 'bar', "name": "dj", 'numbers': [1, 3, 4, 8]}
input2 = {'foo': 'bar', "name": "aj", 'numbers': [1, 3, 7, 8], "extera": "12"}
input3 = {'foo': 'bar', "name": "dj", 'numbers': [1, 3, 4, 8], "extera": "12"}
patch = jsonpatch.JsonPatch.from_diff(doc_in_db, input3)
print("\n***patch***\n", patch)
doc = get_minimal_doc(doc_in_db, patch)
result = patch.apply(doc, in_place=True)
print("\n###result###\n", result,
"\n###present###\n", doc_in_db)
def get_minimal_doc(present, patch):
cur_dc = {}
for change in patch.patch:
if change['op'] not in ("add"):
keys = change['path'].split("/")[1:]
present_move = {}
old_key = 1
first = True
for key in keys:
if key.isdigit(): # old_key represented a array
cur_dc[old_key] = present_move
else:
if first:
cur_dc[key] = {}
first = False
else:
cur_dc[old_key][key] = {}
old_key = key
present_move = present[old_key]
return cur_dc
tryjsonpatch()

How to store Python dictionary with QSettings

The code below stores Python data dictionary using QSettings object.
After reading it back the dictionary comes with all its keys as QString like so:
{PyQt4.QtCore.QString(u'one'): 1, PyQt4.QtCore.QString(u'two'): 2}
I wonder if it would be possible to read the dictionary with a regular string keys like this:
{'one': 1, 'two': 2}
Code:
from PyQt4 import QtCore, QtGui
app = QtGui.QApplication([])
settings = QtCore.QSettings('apps', 'settings')
data = {'one': 1, 'two': 2}
settings.setValue('data', data)
data = settings.value('data').toPyObject()
print data

Python2
Is not possible directly, you have to convert them to a regular dictionary.
d = {}
for k, v in data.items():
d[str(k)] = v
Complete code:
from PyQt4 import QtCore, QtGui
app = QtGui.QApplication([])
settings = QtCore.QSettings('apps', 'settings')
data = {'one': 1, 'two': 2}
settings.setValue('data', data)
data = settings.value('data').toPyObject()
d = {}
for k, v in data.items():
d[str(k)] = v
print(d)
output:
{'two': 2, 'one': 1}
Python3
This problem does not exist since it returns you a regular dictionary, it is no longer necessary to convert it with toPyObject().
from PyQt4 import QtCore, QtGui
app = QtGui.QApplication([])
settings = QtCore.QSettings('apps', 'settings')
data = {'one': 1, 'two': 2}
settings.setValue('data', data)
data = settings.value('data')
print(data)
output:
{'one': 1, 'two': 2}

original = {PyQt4.QtCore.QString(u'one'): 1, PyQt4.QtCore.QString(u'two'): 2}
converted = {str(k): val for k, v in original.items()}

Python: Append Multiple Values for One Key in Nested Dictionary

I have the below list of tuples:
p = [("01","Master"),("02","Node"),("03","Node"),("04","Server")]
I want my output to look like:
y = {
"Master":{"number":["01"]},
"Node":{"number":["02", "03"]},
"Server":{"number":["04"]}
}
I have tried the below code:
y = {}
for line in p:
if line[1] in y:
y[line[1]] = {}
y[line[1]]["number"].append(line[0])
else:
y[line[1]] = {}
y[line[1]]["number"] = [line[0]]
And I get the below error:
Traceback (most recent call last):
File "<stdin>", line 4, in <module>
KeyError: 'number'
How do I solve this?

from collections import defaultdict
d = defaultdict(lambda: defaultdict(list))
for v, k in p:
d[k]["number"].append(v)
print(d)
defaultdict(<function <lambda> at 0x7f8005097578>, {'Node': defaultdict(<type 'list'>, {'number': ['02', '03']}), 'Master': defaultdict(<type 'list'>, {'number': ['01']}), 'Server': defaultdict(<type 'list'>, {'number': ['04']})})
without defaultdict:
d = {}
from pprint import pprint as pp
for v, k in p:
d.setdefault(k,{"number":[]})
d[k]["number"].append(v)
pp(d)
{'Master': {'number': ['01']},
'Node': {'number': ['02', '03']},
'Server': {'number': ['04']}}

It's because you don't initialize your dictionary when needed, and you reset it when not needed.
Try this:
p = [("01","Master"),("02","Node"),("03","Node"),("04","Server")]
y = {}
for (number, category) in p:
if not y.get(category, False):
# initializes your sub-dictionary
y[category] = {"number": []}
# adds the correct number to the sub-dictionary
y[category]["number"].append(number)
Note that using a tuple unpacking for (number, category) in p allows your code to be more readable inside your loop.

You are resetting the dictionary!
for line in p:
if line[1] in y:
#y[line[1]] = {} -- RESET! ["number"] will now disappear.
#.. which leads to error in the next line.
y[line[1]]["number"].append(line[0])
else:
y[line[1]] = {}
y[line[1]]["number"] = [line[0]]
A more pythonic way of achieving the same thing would be by using a defaultdict as demonstrated in other answers.

Do not assign {} to key when key is already present in y.
y = {}
for line in p:
try:
y[line[1]]["number"].append(line[0])
except:
y[line[1]] = {}
y[line[1]]["number"] = [line[0]]
OR
Use defaultdict use:-
>>> from collections import defaultdict
>>> p = [("01","Master"),("02","Node"),("03","Node"),("04","Server")]
>>> d = defaultdict(list)
>>> for k, v in p:
... d[v].append(k)
...
>>> d
defaultdict(<type 'list'>, {'Node': ['02', '03'], 'Master': ['01'], 'Server': ['04']})

Get information from different dict by dict name

I have a data/character_data.py:
CHARACTER_A = { 1: {"level": 1, "name":"Ann", "skill_level" : 1},
2: {"level": 2, "name":"Tom", "skill_level" : 1}}
CHARACTER_B = { 1: {"level": 1, "name":"Kai", "skill_level" : 1},
2: {"level": 2, "name":"Mel", "skill_level" : 1}}
In main.py, I can do this:
from data import character_data as character_data
print character_data.CHARACTER_A[1]["name"]
>>> output: Ann
print character_data.CHARACTER_B[2]["name"]
>>> output: Mel
How do I achieve this?
from data import character_data as character_data
character_type = "CHARACTER_A"
character_id = 1
print character_data.character_type[character_id]["name"]
>>> correct output should be: Ann
I get AttributeError when try use character_type as "CHARACTER_A".

How about this
In [38]: from data import character_data as character_data
In [39]: character_type = "CHARACTER_A"
In [40]: character_id = 1
In [41]: getattr(character_data, character_type)[character_id]["name"]
Out[41]: 'Ann'

You can use locals():
>>> from data.character_data import CHARACTER_A, CHARACTER_B
>>> character_id = 1
>>> character_type = "CHARACTER_A"
>>> locals()[character_type][character_id]["name"]
Ann
Though, think about merging CHARACTER_A and CHARACTER_B into one dict and access this dict instead of locals().
Also, see Dive into Python: locals and globals.

You need to structure your data properly.
characters = {}
characters['type_a'] = {1: {"level": 1, "name":"Ann", "skill_level" : 1},
2: {"level": 2, "name":"Tom", "skill_level" : 1}}
characters['type_b'] = ...
Or, the better solution is to create your own "character" type, and use that instead:
class Character(object):
def __init__(self, type, level, name, skill):
self.type = type
self.level = level
self.name = name
self.skill = skill
characters = []
characters.append(Character('A',1,'Ann',1))
characters.append(Character('A',2,'Tom',1))
characters.append(Character('B',2,'Kai',1)) # and so on
Then,
all_type_a = []
looking_for = 'A'
for i in characters:
if i.type == looking_for:
all_type_a.append(i)
Or, the shorter way:
all_type_a = [i for i in characters if i.type == looking_for]