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How to obtain a value from inside a loop

I will be implementing multiprocessing so that the loops are occurring at the same time, but how can I make it so at the end of each iteration, I can obtain the value of westernEurope.cases and easternEurope.cases so that I can add them together
westernEurope = Region("Western Europe", 1000, 0, 0, 8, 4, 4, 0)
while westernEurope.deaths < westernEurope.population:
westernEurope.infection()
if westernEurope.cases > westernEurope.population:
westernEurope.cases = westernEurope.population
print("Infections:", westernEurope.cases)
westernEurope.death()
if westernEurope.deaths > westernEurope.population:
westernEurope.deaths = westernEurope.population
print("Deaths:", westernEurope.deaths)
#where i want to return the value of westernEurope.cases
time.sleep(0.1)
easternEurope = Region("Eastern Europe", 1000, 0, 0, 8, 4, 4, 0)
while easternEurope.deaths < easternEurope.population:
easternEurope.infection()
if easternEurope.cases > easternEurope.population:
easternEurope.cases = easternEurope.population
print("Infections:", easternEurope.cases)
easternEurope.death()
if easternEurope.deaths > easternEurope.population:
easternEurope.deaths = easternEurope.population
print("Deaths:", easternEurope.deaths)
# where i want to return the value of easternEurope.cases
time.sleep(0.1)
print(easternEurope.cases + westernEurope.cases)

IMHO there is no need for multiprocessing. With a generator, your problem can be solved in an even more elgant way.
# where i want to return the value of easternEurope.cases
yield region.cases
Full code:
def desease(region: Region):
while region.deaths < region.population:
region.infection()
if region.cases > region.population:
region.cases = region.population
print("Infections:", region.cases)
region.death()
if region.deaths > region.population:
region.deaths = region.population
print("Deaths:", region.deaths)
# where i want to return the value of easternEurope.cases
yield region.cases
time.sleep(0.1)
easternEurope = Region("Eastern Europe", 1000, 0, 0, 8, 4, 4, 0)
westernEurope = Region("Western Europe", 2000, 0, 0, 8, 4, 4, 0)
eastDesease = desease(easternEurope)
westDesease = desease(westernEurope)
for eastCases, westCases in zip(eastDesease, westDesease):
print(eastCases, westCases)

How to fix "AttributeError: type object has no attribute" in python?

I am adding some code to the preset code to check the time availability, which is if the meeting time can fit into the proposed time schedule. However, I keep getting the following error. Can anyone please give me some advices? Thanks so much for your time.
Preset codes:
from datetime import datetime
class Meeting:
def __init__(self, start_time, end_time):
self.start_time = start_time
self.end_time = end_time
My codes:
def check_availability(meetings, proposed_time):
meeting_start = Meeting.datetime.start_time.hour
meeting_end = Meeting.datetime.end_time.hour
ok_time = datetime.proposed_time.hour
if meeting_start < ok_time < meeting_end:
return True
else:
return False
meetings = [Meeting(datetime(2018, 8, 1, 9, 0, 0), datetime(2018, 8, 1, 11,
0, 0)), Meeting(datetime(2018, 8, 1, 15, 0, 0), datetime(2018, 8, 1, 16, 0,
0)), Meeting(datetime(2018, 8, 2, 9, 0, 0), datetime(2018, 8, 2, 10, 0, 0))]
print(check_availability(meetings, datetime(2018, 8, 1, 12, 0, 0)))
print(check_availability(meetings, datetime(2018, 8, 1, 10, 0, 0)))

Your code raises this exception:
AttributeError: type object 'Meeting' has no attribute 'datetime'
At this line:
meeting_start = Meeting.datetime.start_time.hour
Python is telling you that the Meeting class doesn't have an attribute named datetime. This is true: the Meeting class is a factory for making meeting objects (or instances), and these objects have start_time and end_time attributes, which are set by passing datetime instances to Meeting's __init__ method. These attributes can be accessed like this:
>>> meeting = Meeting(datetime(2018, 8, 1, 9, 0, 0), datetime(2018, 8, 1, 11,
0, 0))
>>> print(meeting.start_time)
2018-08-01 09:00:00
>>> print(meeting.end_time)
2018-08-01 11:00:00
Your check_availability function is being passed a list of meetings, so you need to loop over the list to check whether any of the meetings conflict with the proposed meeting time.
def check_availability(meetings, proposed_time):
# Loop over the list of meetings; "meeting"
# is the meeting that you are currently inspecting.
for meeting in meetings:
# if proposed_time is between meeting.start_time
# and meeting.end_time, return False
# If you get through the list without returning False
# then the proposed time must be ok, so return True.

Changing keys in dictionary

How can I change the keys of a dictionary of lists to display dates (outright) rather than datetime.date(2017, 1, 1) which is what they currently are formatted as?
Example of section of list:
{datetime.date(2017, 9, 7): [162.3, 163.24, 162.22, 163.18], datetime.date(2017, 7, 10): [160.44, 161.13, 160.44, 160.94],
I am rather new to python so any help would be much appreciated. Thanks.

call the strftime method for each datetime object:
import datetime
s = {datetime.date(2017, 9, 7): [162.3, 163.24, 162.22, 163.18], datetime.date(2017, 7, 10): [160.44, 161.13, 160.44, 160.94]}
new_s = {a.strftime("%Y-%m-%d"):b for a, b in s.items()}
Output:
{'2017-07-10': [160.44, 161.13, 160.44, 160.94], '2017-09-07': [162.3, 163.24, 162.22, 163.18]}

Try this:
import datetime
my_dict = {datetime.date(2017, 9, 7): [162.3, 163.24, 162.22, 163.18], datetime.date(2017, 7, 10): [160.44, 161.13, 160.44, 160.94]}
new_dict = {str(k): v for k,v in my_dict.items()}
Output:
{'2017-07-10': [160.44, 161.13, 160.44, 160.94],
'2017-09-07': [162.3, 163.24, 162.22, 163.18]}

How to use a loop to create radiobuttons in Python

I have to create multiple radio buttons. Each has its own name and location on grid. There are also several variables involved.
I stored all the data to create these radio buttons in a tuple
(I know that FONTS does not cause a problem, its stored above this but isn't shown here):
self.unitType = IntVar()
self.matPropSel = IntVar()
self.secProfSel = IntVar()
self.endSupSel = IntVar()
self.loadTypeSel = IntVar()
self.RADIOLABELS = ( # Text, Font, Variable, Value, Row, Column
('English', self.FONTS[3], self.unitType, 1, 3, 1),
('metric', self.FONTS[3], self.unitType, 2, 4, 1),
('select preset', self.FONTS[3], self.matPropSel, 1, 6, 1),
('manual entry', self.FONTS[3], self.matPropSel, 2, 7, 1),
('select preset', self.FONTS[3], self.secProfSel, 1, 10, 1),
('manual entry', self.FONTS[3], self.secProfSel, 2, 11, 1),
('one end', self.FONTS[3], self.endSupSel, 1, 15, 1),
('both ends', self.FONTS[3], self.endSupSel, 2, 16, 1),
('point', self.FONTS[3], self.loadTypeSel, 1, 18, 1),
('uniform distribution', self.FONTS[3], self.loadTypeSel, 2, 19, 1),
('uniform variation', self.FONTS[3], self.loadTypeSel, 3, 20, 1)
)
So, how would I use a for loop to go through this tuple and generate a radio button from each line? Do all of the variables have to be the same? I am having problems with them.
Here is my attempt at a loop:
outerIndexer = 0
for labels in self.RADIOLABELS:
Radiobutton(self, text=self.RADIOLABELS[outerIndexer][0], font=self.RADIOLABELS[outerIndexer][1],
variable=self.RADIOLABELS[outerIndexer][2], value=self.RADIOLABELS[outerIndexer][3])\
.grid(row=self.RADIOLABELS[outerIndexer][4], column=self.RADIOLABELS[outerIndexer][5])
outerIndexer += 1

You can do it like this by looping through the RADIOLABELS. Note: it is also recommended to save the button to a list so it doesn't get lost.
self.RADIOLABELS = ( # Text, Font, Variable, Value, Row, Column
('English', self.FONTS[3], self.unitType, 1, 3, 1),
('metric', self.FONTS[3], self.unitType, 2, 4, 1),
('select preset', self.FONTS[3], self.matPropSel, 1, 6, 1),
('manual entry', self.FONTS[3], self.matPropSel, 2, 7, 1),
('select preset', self.FONTS[3], self.secProfSel, 1, 10, 1),
('manual entry', self.FONTS[3], self.secProfSel, 2, 11, 1),
('one end', self.FONTS[3], self.endSupSel, 1, 15, 1),
('both ends', self.FONTS[3], self.endSupSel, 2, 16, 1),
('point', self.FONTS[3], self.loadTypeSel, 1, 18, 1),
('uniform distribution', self.FONTS[3], self.loadTypeSel, 2, 19, 1),
('uniform variation', self.FONTS[3], self.loadTypeSel, 3, 20, 1)
)
radiobuttons = []
for _Text, _Font, _Variable, _Value, _Row, _Column in self.RADIOLABELS: # it will unpack the values during each iteration
_Radio = tk.Radiobutton(root, text = _Text, font = _Font, variable = _Variable, value = _Value)
# ^ root should be the frame/Tk you're trying to place it on, it will be self if this is a direct subclass of a Frame or Tk
# ^ or Radiobutton(.....) if you did from tkinter import *
_Radio.grid(row = _Row, column = _Column)
radiobuttons.append(_Radio)

Why does this Python code get the name error? [duplicate]

This question already has answers here:
Accessing class variables from a list comprehension in the class definition
(8 answers)
Closed 7 years ago.
I want to have attribute that is shared by and accessible to all instances of a class.
Sample code:
class Test:
code = [ 1, 2, 3, 5, 6, 7, 8, 9, 10]
code2d = [ [ code[j*3 + i] for i in range(3) ] for j in range(3) ]
def __init__(self):
pass
However, I get error:
NameError: name 'code' is not defined
If I put the lines with code and code2d into init method, all is working properly.
Why this code throws the error?

code is a class variable , and hence when accessing it you need to call - Test.code , you cannot access them using code .
Also, even if you do access them using Test.code , it would still not work, because the value for class variables (default value) is calculated when the class is being defined, so when you try to access Test.code , you would not be able to access Test as it has not been created yet. Example of that -
>>> class Test:
... code = [ 1, 2, 3, 5, 6, 7, 8, 9, 10]
... code2d = [ [ Test.code[j*3 + i] for i in range(3) ] for j in range(3) ]
... def __init__(self):
... pass
...
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "<stdin>", line 3, in Test
File "<stdin>", line 3, in <listcomp>
File "<stdin>", line 3, in <listcomp>
NameError: name 'Test' is not defined
I am guessing when you put them in the __init__() you are putting them as -
class Test:
def __init__(self):
code = [ 1, 2, 3, 5, 6, 7, 8, 9, 10]
code2d = [ [ code[j*3 + i] for i in range(3) ] for j in range(3) ]
This would work, because code here is a local variable and hence can be accesed by the other local variables in the __init__() method , though they would not be accessible outside this function.
Maybe, you do not need them as class variables , if you want to have code and code2d for all instances of the class (objects of the class) , you should create instance variable as-
>>> class Test:
... def __init__(self):
... self.code = [ 1, 2, 3, 5, 6, 7, 8, 9, 10]
... self.code2d = [ [ self.code[j*3 + i] for i in range(3) ] for j in range(3) ]
If you really want code and code2d to be class variables , one way to do it would be to define code2d outside the class Test , example -
class Test:
code = [ 1, 2, 3, 5, 6, 7, 8, 9, 10]
def __init__(self):
pass
Test.code2d = [ [ Test.code[j*3 + i] for i in range(3) ] for j in range(3) ]