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How to print specific data from JSON file lists in a line break layout?

Take this example:
"something": {
"random": 0,
"bag": {
"papers": 0,
"pencils": 0
},
"PAINT": {
"COLORS": [
"A WHITE",
"B MAPLE",
"B LOTUS",
"A OLIVE"
],
"CANS": [
"SOMETHING"
]
}
Ignore everything and focus on the COLORS list in the PAINT dictionary... I want to print all colors that have the color A before them, as a code. In other words I want to print "A WHITE" and "A OLIVE". Here's what happens when I do this:
with open("somethings.json", "r") as f:
data = json.load(f)
print(data["something"]["PAINT"]["COLORS"])
This is the output:
["A WHITE", "B MAPLE", "B LOTUS", "A OLIVE"]
but like I said, I do not want that... I want only A colors to be printed...
I also do not want THIS:
["A WHITE", "A OLIVE"]
the output that I really want (which is quite specific) is this:
OLIVE
WHITE
With line breaks (optional: AND in alphabetical order) that is the output that I want. So how can I print this output? is it possible without using any 'for' loops? This is a very specific question, would appreciate some help. Thanks -

Try this code:
with open("somethings.json", "r") as f:
data = json.load(f)
a_colors = [color for color in data["something"]["PAINT"]["COLORS"] if color.startswith("A ")]
colors = [a_color.replace("A ", "") for a_color in a_colors]
print(colors)
How it works
Opens and loads the JSON data.
Uses a list comprehension to filter only entries that start with "A ".
The .startswith() method of a string returns a boolean value, True if the first few characters of the string are, in fact, the characters passed as an argument, and False otherwise.
Uses another list comprehension to get the string without the "A " for each string in the list created in step 2.
Replaces the "A " with an empty string, which is a hacky way of deleting part of a string using the .replace() method.
It can be done without list comprehensions using a for loop as well
See code below:
with open("somethings.json", "r") as f:
data = json.load(f)
a_colors = []
for color in data["something"]["PAINT"]["COLORS"]:
if color.startswith("A "):
color_without_a = color.replace("A ", "")
a_colors.append(color_without_a)
print(a_colors)
This solution uses a for loop rather than a list comprehension but is otherwise the same. (If you are confused, see below for a solution which is an exact replica of the list comprehension one but implemented with for loops).
If you are interested, here is a lengthier solution more similar to the list comprehension one, using for loops:
with open("somethings.json", "r") as f:
data = json.load(f)
a_colors = []
for color in data["something"]["PAINT"]["COLORS"]:
if color.startswith("A "):
a_colors.append(color)
colors = []
for a_color in a_colors:
colors.append(a_color.replace("A ", ""))
print(colors)
To sort alphabetically, use the sorted() function, like this for the list comprehension solution and the second for loop solution:
sorted_list = sorted(colors)
print(sorted_list)
For the first for loop solution:
sorted_list = sorted(a_colors)
print(sorted_list)
Recommended reading
Python Data Structures documentation
Examples of list comprehensions for practice
Beginner's list comprehension tutorial
Filtering lists in Python
Other helpful resources
List slicing
Sorting Lists
I strongly recommend watching this video as well:
Python Tutorial for Beginners 7: Loops and Iterations - For/While Loops

Well, you can't really don't use a for-loop, you need to iterate over all elements in your COLORS array.
So, what you want to do is:
Iterate over all elements
Check if the first character of each element (e.g. A WHITE) is the desired character (e.g. A)
either print the output directly or store it in list without the A (notice the space)
So:
with open("somethings.json", "r") as f:
data = json.load(f)
colors = data["something"]["PAINT"]["COLORS"]
best_colors = []
for color in colors:
if color[0] == "A": # or any character you want; CASE SENSITIVE!
best_colors.append(color[2:]) # this adds the color without the A and the space to the list
# Optionally: Sort alphabetically
sorted_colors = sorted(best_colors)
Additional resources to help you to understand the code better:
List slicing
Sorting Lists

Based on Unix Doughnut's answer:
# Read JSON File
with open("file_name.json", "r") as f:
data = json.load(f)
# Sort the selected elements starting with A without the leading A
colors = sorted([color.replace("A ", "") for color in data["something"]["PAINT"]["COLORS"] if color.startswith("A ")])
# Print list elements separated by line break ( without for loop )
print(*colors, sep='\n')`

Remove Prefixes From a String

What's a cute way to do this in python?
Say we have a list of strings:
clean_be
clean_be_al
clean_fish_po
clean_po
and we want the output to be:
be
be_al
fish_po
po

Another approach which will work for all scenarios:
import re
data = ['clean_be',
'clean_be_al',
'clean_fish_po',
'clean_po', 'clean_a', 'clean_clean', 'clean_clean_1']
for item in data:
item = re.sub('^clean_', '', item)
print (item)
Output:
be
be_al
fish_po
po
a
clean
clean_1

Here is a possible solution that works with any prefix:
prefix = 'clean_'
result = [s[len(prefix):] if s.startswith(prefix) else s for s in lst]

You've merely provided minimal information on what you're trying to achieve, but the desired output for the 4 given inputs can be created via the following function:
def func(string):
return "_".join(string.split("_")[1:])

you can do this:
strlist = ['clean_be','clean_be_al','clean_fish_po','clean_po']
def func(myList:list, start:str):
ret = []
for element in myList:
ret.append(element.lstrip(start))
return ret
print(func(strlist, 'clean_'))
I hope, it was useful, Nohab

There are many ways to do based on what you have provided.
Apart from the above answers, you can do in this way too:
string = 'clean_be_al'
string = string.replace('clean_','',1)
This would remove the first occurrence of clean_ in the string.
Also if the first word is guaranteed to be 'clean', then you can try in this way too:
string = 'clean_be_al'
print(string[6:])

You can use lstrip to remove a prefix and rstrip to remove a suffix
line = "clean_be"
print(line.lstrip("clean_"))
Drawback:
lstrip([chars])
The [chars] argument is not a prefix; rather, all combinations of its values are stripped.

Question about String operations in Python

I am new to Python, and was practising File Operations. I have written this program:
myfile = open('test3.txt', 'w+')
myfile.writelines(['Doctor', 'Subramanian', 'Swamy', 'Virat', 'Hindustan', 'Sangam'])
which outputs the following:
DoctorSubramanianSwamyViratHindustanSangam.
How do I add spaces in between items of the list in the final output such that the final output is Doctor Subramanian Swamy Virat Hindustan Sangam?

Based on what I understood from your question, you wish to add spaces between elements of the list in the final output. One possible solution is:
myfile = open('test3.txt', 'w+')
list = ['Doctor', 'Subramanian', 'Swamy', 'Virat', 'Hindustan', 'Sangam']
for l in list:
myfile.write(l+' ')
In particular, this line myfile.write(l+' ') will add a space after writing every element.

You could try stripping it using the same .strip() method?
value = "'"
list1 = []
for item in list2:
list1.append(item.strip("{0}".format(value)))
try it and let me know

How to turn a list containing strings into a list containing integers (Python)

I am optimizing PyRay (https://github.com/oscr/PyRay) to be a usable Python ray-casting engine, and I am working on a feature that takes a text file and turns it into a list (PyRay uses as a map). But when I use the file as a list, it turns the contents into strings, therefore not usable by PyRay. So my question is: How do I convert a list of strings into integers? Here is my code so far. (I commented the actual code so I can test this)
print("What map file to open?")
mapopen = input(">")
mapload = open(mapopen, "r")
worldMap = [line.split(',') for line in mapload.readlines()]
print(worldMap)
The map file:
1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,
1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,
2,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,
1,0,2,0,0,3,0,0,0,0,0,0,0,2,3,2,3,0,0,2,
2,0,3,0,0,2,0,0,0,0,0,0,0,0,0,0,0,0,0,1,
1,0,0,0,0,3,0,0,0,0,0,0,0,0,0,0,0,0,0,2,
2,3,1,0,0,2,0,0,0,2,3,2,0,0,0,0,0,0,0,1,
1,0,0,0,0,0,0,0,0,1,0,1,0,0,1,2,0,0,0,2,
2,0,0,0,0,0,0,0,0,2,0,2,0,0,2,1,0,0,0,1,
1,0,0,0,0,0,0,0,0,1,3,1,0,0,0,0,0,0,0,2,
2,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,
1,0,2,0,0,3,0,0,0,0,0,0,0,0,0,0,0,0,0,2,
2,0,3,0,0,2,0,0,0,0,0,0,0,2,3,2,1,2,0,1,
1,0,0,0,0,3,0,0,0,0,0,0,0,1,0,0,2,0,0,2,
2,3,1,0,0,2,0,0,2,1,3,2,0,2,0,0,3,0,3,1,
1,0,0,0,0,0,0,0,0,3,0,0,0,1,0,0,2,0,0,2,
2,0,0,0,0,0,0,0,0,2,0,0,0,2,3,0,1,2,0,1,
1,0,0,0,0,0,0,0,0,1,0,0,0,1,0,0,0,3,0,2,
2,0,0,0,0,0,0,0,0,0,0,0,0,0,0,3,0,0,0,1,
2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,
Please help me, I have been searching all about and I can't find anything.

try this: Did you want a list of lists? or just one big list?
with open(filename, "r") as txtr:
data = txtr.read()
data = txtr.split("/n") # split into list of strings
data = [ list(map(int, x.split(","))) for x in data]
fourth line splits string into list by removing comma, then appliea int() on each element then turns it into a list. It does this for every element in data. I hope it helps.
Here is for just one large list.
with open(filename, "r") as txtr:
data = txtr.readlines() # remove empty lines in your file!
data = ",".join(data) # turns it into a large string
data = data.split(",") # now you have a list of strings
data = list(map(int, data)) # applies int() to each element in data.

Look into the map built-in function in python.
L=['1', '2', '3']
map = map(int, L)
for el in map:
print(el)
>>> 1
... 2
... 3

As per you question, please find below a way you can change list of strings to list of integers (or integers if you use list index to get the integer value). Hope this helps.
myStrList = ["1","2","\n","3"]
global myNewIntList
myNewIntList = []
for x in myStrList:
if(x != "\n"):
y = int(x)
myNewIntList.append(y)
print(myNewIntList)

Python Joining List and adding and removing characters

I have a list i need to .join as string and append characters
my_list = ['3.3.3.3', '2.2.2.3', '2.2.2.2']
my_list.append(')"')
my_list.insert(0,'"(')
hostman = '|'.join('{0}'.format(w) for w in my_list)
#my_list.pop()
print(hostman)
print(my_list)
My output = "(|3.3.3.3|2.2.2.3|2.2.2.2|)"
I need the output to be = "(3.3.3.3|2.2.2.3|2.2.2.2)"
how can i strip the first and last | from the string

You are making it harder than it needs to be. You can just use join() directly with the list:
my_list = ['3.3.3.3', '2.2.2.3', '2.2.2.2']
s = '"(' + '|'.join(my_list) + ')"'
# s is "(3.3.3.3|2.2.2.3|2.2.2.2)"
# with quotes as part of the string
or if you prefer format:
s = '"({})"'.format('|'.join(my_list))

Try this :
hostman = "("+"|".join(my_list)+")"
OUTPUT :
'(3.3.3.3|2.2.2.3|2.2.2.2)'