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Difficulty understanding changes to dictionary

I was looking through old posts in order to find a method of changing values in a dictionary by iterating through the items.
dictionary = {
1: [
{
"id": "1234",
"cow": "parts/sizes/lakes"
},
{
"id": "5151",
"cow": "minors/parts"
}
]}
def fetchanswers():
for item in dictionary[1]:
yield(item["id"], item["cow"])
for a, b in fetchanswers():
k = {}
k["id"] = a
k["cow"] = b.replace("parts", a)
My understanding is that yield returns the two items from either object in the dictionary and the for loop creates a new dictionary and appends the values obtained from fetchanswers() and parts is replaced by id.
I don't understand how k["id"] can be referred to when the dictionary is empty.

a method of changing values in a dictionary
Your values are strings. Strings are immutable, so you need to overwrite the dictionary using existing keys
You don't need another dictionary for this
# replace "parts" text value with the value of the id key
for item in list_of_dicts:
item["cow"] = item["cow"].replace("parts", str(item["id"]))
how k["id"] can be referred to
It's not a referral when there's an equal sign afterwards. It's an assignment

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"]}

Python - add a list of dictionary in a dictionary

So I have a dictionary called component and a list of dictionaries called allocations.
I want to be able to put the allocations under a component as a nested dictionary. kind of like so:
Allocations[
allocation1 : {
key : value
},
allocation2 {
key : value
}
]
My desired output:
Component1 : {
key:value
allocations : [allocation1 : {
key : value
}
,allocation2 : {
key : value
}
]
}
I came from Java, and i realize there is no append that I can use.
I tried this and obviously didnt work:
#allocate this under the selected component - DIDNT WORK
component["allocations"][] = allocation
How can I create a list of dictionaries in a dictionary?

Simply assign it:
component["allocations"] = some_list
For instance, if you want a new, empty one:
component["allocations"] = []
or:
component["allocations"] = list()
Then, manipulate the list as usual:
component["allocations"].append(some_object)

creating nested json objects from a list

I am attempting to understand how to take a list and convert that into a nested JSON object.
Expected Output
{
"Name1": [
{
"key": "value",
"key": "value",
"key": "value",
"key": "value"
}
],
}
So far my thinking as gone as follows, convert the list to dictionary using comprehension and splitting key value pairs.
list1 = ['key value', 'key value', 'key value']
dict1 = dict(item.split(" ") for item in list1)
I then thought converting that into a JSON object would be something similar to:
print json.loads(dict1)
However, Im not sure how to create the "Name1" parent key. And it seems google is being particularly helpful. Im sure there is something simple im missing, any pointers would be appreacited.
EDIT
Included a list for reference

You simply put them in another dictionary, and use a new list. So:
import json
list1 = ['key1 value1', 'key2 value2', 'key3 value3']
dict1 = {'Name1': [dict(item.split(" ",1) for item in list1)] }
# ^ dict ^ list with 1 element end list ^ ^ end dict
json.dumps(dict1)
And this produces:
>>> print(json.dumps(dict1))
{"Name1": [{"key2": "value2", "key3": "value3", "key1": "value1"}]}
Notes:
A dictionary can only contain different keys (both in JSON and Python);
You better split with .split(" ",1) since if the value contains spaces, these are all seen as still a single value.
dictionaries are unordered, so the order of th keys can be shuffled.

For each loop with JSON object python

Alright, so I'm struggling a little bit with trying to parse my JSON object.
My aim is to grab the certain JSON key and return it's value.
JSON File
{
"files": {
"resources": [
{
"name": "filename",
"hash": "0x001"
},
{
"name": "filename2",
"hash": "0x002"
}
]
}
}
I've developed a function which allows me to parse the JSON code above
Function
def parsePatcher():
url = '{0}/{1}'.format(downloadServer, patcherName)
patch = urllib2.urlopen(url)
data = json.loads(patch.read())
patch.close()
return data
Okay so now I would like to do a foreach statement which prints out each name and hash inside the "resources": [] object.
Foreach statement
for name, hash in patcher["files"]["resources"]:
print name
print hash
But it only prints out "name" and "hash" not "filename" and "0x001"
Am I doing something incorrect here?

By using name, hash as the for loop target, you are unpacking the dictionary:
>>> d = {"name": "filename", "hash": "0x001"}
>>> name, hash = d
>>> name
'name'
>>> hash
'hash'
This happens because iteration over a dictionary only produces the keys:
>>> list(d)
['name', 'hash']
and unpacking uses iteration to produce the values to be assigned to the target names.
That that worked at all is subject to random events even, on Python 3.3 and newer with hash randomisation enabled by default, the order of those two keys could equally be reversed.
Just use one name to assign the dictionary to, and use subscription on that dictionary:
for resource in patcher["files"]["resources"]:
print resource['name']
print resource['hash']

So what you intend to do is :
for dic in x["files"]["resources"]:
print dic['name'],dic['hash']
You need to iterate on those dictionaries in that array resources.

The problem seems to be you have a list of dictionaries, first get each element of the list, and then ask the element (which is the dictionary) for the values for keys name and hash
EDIT: this is tested and works
mydict = {"files": { "resources": [{ "name": "filename", "hash": "0x001"},{ "name": "filename2", "hash": "0x002"}]} }
for element in mydict["files"]["resources"]:
for d in element:
print d, element[d]

If in case you have multiple files and multiple resources inside it. This generalized solution works.
for keys in patcher:
for indices in patcher[keys].keys():
print(patcher[keys][indices])
Checked output from myside
for keys in patcher:
... for indices in patcher[keys].keys():
... print(patcher[keys][indices])
...
[{'hash': '0x001', 'name': 'filename'}, {'hash': '0x002', 'name': 'filename2'}]