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Iterating through a json in python - only wanting the value for one key in multiple dicts

I have this Json file, and I want to get the "navn" out with a iterating.
I need it to print:
Traktor
Bil and nothing else, how do I do that ?
[
{"navn": "Traktor", "år": 10, "købspris": 10000},
{"navn": "Bil", "år": 20, "købspris": 100000},
{},
{}
]
So far I have this idea
I know I need to import json file, and iterating through it but every time it gives me a error... I have tried searching the whole wide web and nothing came up
my code so far:
import json
def main():
f = open("/Users/maltheschroderjakobsen/Desktop/coding/test/mat.json",)
f = json.load(f)
for key in f["navn"]:
print (key)
main()
But every time I try anything else it gives me a error

f seems to be a list, not a dictionary:
for dct in f:
if "navn" in dct: # the elements are dicts!
print(dct["navn"])

It's because some dicts have no key navn. Use dict.get instead:
import json
def main():
file = open("/Users/maltheschroderjakobsen/Desktop/coding/test/mat.json",)
data = json.load(file)
for dct in data:
print(dct.get("navn", ""))
main()

So long as the JSON only has dicts, you can do:
js='''\
[
{"navn": "Traktor", "år": 10, "købspris": 10000},
{"navn": "Bil", "år": 20, "købspris": 100000},
{},
{}
]'''
import json
>>> [e['navn'] for e in json.loads(js) if e.get('navn', '')]
['Traktor', 'Bil']
JSON can also have other datatypes such as lists or numeral. If there is a possibility of something other than a dict in the JSON, you can do:
[e['navn'] for e in json.loads(js) if isinstance(e, dict) and e.get('navn', '')]

How to append the list of dictionary to same list in python?

I'm having a JSON with nested values. I need to remove the key of the nested field and need to keep the values as plain JSON.
JSON(Structure of my JSON)
[
{
"id":"101",
"name":"User1",
"place":{
"city":"City1",
"district":"District1",
"state":"State1",
"country":"Country1"
},
"access":[{"status":"available"}]
}
]
I need to get the JSON output as:
Expected Output:
[
{
"id":"101",
"name":"User1",
"city":"City1",
"district":"District1",
"state":"State1",
"country":"Country1"
"access":[{"status":"available"}]
}
]
What i need is:
I need to parse the JSON
Get the Placefield out of the JSON
Remove the key and brackets and append the values to existing
Python
for i in range(0,len(json_data)):
place_data = json_data[i]['place']
print(type(place_data)) #dict
del place_data['place']
Any approach to get the expected output in python.?

One way to accomplish this could be by
for i in json_data:
i.update(i.pop("place"))

Another way to accomplish this with multiple "keys" updated...
This would only work for a single nested level as described in the original question
def expand(array):
flatten = list()
for obj in array:
temp = {}
for key, value in obj.items():
if isinstance(value, dict):
temp.update(value)
else:
temp.update({key:value})
flatten.append(temp)
return flatten

Python remove from json dict doesn't work

When i call this function to remove an item from a dict imported from json it doesn't work
def removeKey(key):
with open ("keys.json") as f:
data = json.loads(f.read())
for d in data["keys"]:
if(d["key"] == key):
del d
print(data)
with open ("keys.json", "w") as f:
json.dump(data, f)
This is how the dict is set up in JSON
{"keys": [
{"key": 1599853953652, "role": "MODERATOR", "Server": 753230650181550141, "uses": 1, "maxuses": 0}
]
}

It seems like you actually want to remove any dictionaries in the list of dicts under "keys" if the value of their "key" entry matches a certain number (e.g. 1599853953652).
Assuming that's the case, the cleanest approach is actually to create a new list that filters out the unwanted entries; you can't simply call del to remove an element while iterating.
data = json.loads(f.read())
filtered_keys = [d for d in data["keys"] if d["key"] != key]
data["keys"] = filtered_keys

remove 'role' - one liner demo
data = {"keys": [
{"key": 1599853953652, "role": "MODERATOR", "Server": 753230650181550141, "uses": 1, "maxuses": 0}
]
}
data['keys'][0].pop('role',None)
print(data)
output
{'keys': [{'key': 1599853953652, 'Server': 753230650181550141, 'uses': 1, 'maxuses': 0}]}

Using del d only deletes the variable d but doesn't affect the list you want to remove from. You need operate on the list itself. I would use the pop() method, although del would work too.
def removeKey(key):
with open ("keys.json") as f:
data = json.loads(f.read())
for i, d in enumerate(data["keys"]):
if d["key"] == key:
data["keys"].pop(i)
print(data)
with open ("keys.json", "w") as f:
json.dump(data, f)

for d in data["keys"]:
if(d["key"] == key):
del d
del deletes names. Deleting a name does not delete the associated value, unless it was the only name for the value.
The for d in ... loop creates d as an additional name for data["keys"]["key"]. When you del d, you are only deleting the name d -- you are not deleting the value from data.
This is equivalent to:
x = 1
y = x
del y
After running this code, x still exists. del y just removed the name y.
To put it another way, think of post-it notes stuck onto boxes. The post-it notes are names, and the boxes are values. One box can have many notes stuck on it, and removing a note doesn't destroy the box (unless it was the only note).

Remove entire JSON object if it contains a specified phrase (from a list in python)

Have a JSON file output similar to:
{
"object1": {
"json_data": "{json data information}",
"tables_data": "TABLES_DATA"
},
"object2": {
"json_data": {json data information}",
"tables_data": ""
}
}
Essentially, if there is an empty string for tables_data as shown in object2 (eg. "tables_data": ""), I want the entire object to be removed so that the output would look like:
{
"object1": {
"json_data": "{json data information}",
"tables_data": "TABLES_DATA"
}
}
What is the best way to go about doing this? Each of these objects correspond to a separate index in a list that I've appended called summary[].

To achieve this, you could iterate through the JSON dictionary and test the tables_data values, adding the objectX elements to a new dictionary if their tables_data value passes the test:
new_dict = {k: v for k, v in json_dict.items()
if v.get("tables_data", "") != ""}
If your JSON objectX is stored in a list as you say, these could be processed as follows using a list comprehension:
filtered_summary = [object_dict for object_dict in summary
if object_dict.get("tables_data", "") != ""]

Unless you have compelling reasons to do otherwise, the pythonic way to filter out a list or dict (or any iterable) is not to change it in place but to create a new filtered one. For your case this would look like
raw_data = YOUR_DICT_HERE_WHEREVER_IT_COMES_FROM
# NB : empty string have a false value in a boolean test
cleaned_data = {k:v for k, v in raw_data.items() if not v["table_data"]}

How do I iterate through nested dictionaries in a list of dictionaries?

Still new to Python and need a little help here. I've found some answers for iterating through a list of dictionaries but not for nested dictionaries in a list of dictionaries.
Here is the a rough structure of a single dictionary within the dictionary list
[{ 'a':'1',
'b':'2',
'c':'3',
'd':{ 'ab':'12',
'cd':'34',
'ef':'56'},
'e':'4',
'f':'etc...'
}]
dict_list = [{ 'a':'1', 'b':'2', 'c':'3', 'd':{ 'ab':'12','cd':'34', 'ef':'56'}, 'e':'4', 'f':'etc...'}, { 'a':'2', 'b':'3', 'c':'4', 'd':{ 'ab':'23','cd':'45', 'ef':'67'}, 'e':'5', 'f':'etcx2...'},{},........,{}]
That's more or less what I am looking at although there are some keys with lists as values instead of a dictionary but I don't think I need to worry about them right now although code that would catch those would be great.
Here is what I have so far which does a great job of iterating through the json and returning all the values for each 'high level' key.
import ujson as json
with open('test.json', 'r') as f:
json_text = f.read()
dict_list = json.loads(json_text)
for dic in dict_list:
for val in dic.values():
print(val)
Here is the first set of values that are returned when that loop runs
1
2
3
{'ab':'12','cd':'34','ef':'56'}
4
etc...
What I need to be able to do pick specific values from the top level and go one level deeper and grab specific values in that nested dictionary and append them to a list(s). I'm sure I am missing a simple solution. Maybe I'm looking at multiple loops?

Following the ducktype style encouraged with Python, just guess everything has a .values member, and catch it if they do not:
import ujson as json
with open('test.json', 'r') as f:
json_text = f.read()
dict_list = json.loads(json_text)
for dic in dict_list:
for val in dic.values():
try:
for l2_val in val.values():
print(l2_val)
except AttributeError:
print(val)
Bazingaa's solution would be faster if inner dictionaries are expected to be rare.
Of course, any more "deep" and you would need some recursion probably:
def print_dict(d):
for val in d.values():
try:
print_dict(val)
except AttributeError:
print(val)

How about checking for the instance type using isinstance (of course only works for one level deeper). Might not be the best way though
for dic in dict_list:
for val in dic.values():
if not isinstance(val, dict):
print(val)
else:
for val2 in val.values():
print (val2)
# 1
# 2
# 3
# 12
# 34
# 56
# 4
# etc...
# 2
# 3