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My list gets suddenly empty and I can't restore it

I'm newbie in django and I was trying to construct a site in which the user can take a quiz. In a simpler version of that, I wanted just the questions to be displayed in random order, one after another(when the user presses a button) and when all the questions have been displayed to return to the main page, where there is a link "take the test".
I know that it certainly isn't the most efficient way to do it, but I want to know what is wrong with my code.
urls.py:
path('start',views.startquiz,name='start'),
path('test/<int:pk>/<int:index>',views.TakeQuizView.as_view(),name='test'),
views.py:
def startquiz(request):
questions=list(Question.objects.all())
question=random.choice(questions)
pk=question.id
return redirect(reverse('quiz:test',args=(pk,1)))
class TakeQuizView(LoginRequiredMixin,View):
questions=list(Question.objects.all())
n=len(questions)
def get(self,request,pk,index):
question=Question.objects.get(id=pk)
self.questions.remove(question)
ctx={'question':question,'index':index,'n':self.n}
return render(request,'quiz/test.html',ctx,)
def post(self,request,pk,index):
if index<self.n:
question=random.choice(self.questions)
pk=question.id
return redirect(reverse('quiz:test',args=(pk,index+1)))
else:
self.questions=list(Question.objects.all())
return redirect(reverse_lazy('quiz:main'))
`
Whenever I take the quiz for the first time, all works fine, and after all questions have been displayed, it returns to the main page. However, if I want to take the test again, the questions list fails to be filled up again and I get an error: list.remove(x): x not in list from remove()
I also tried to put in the get method the following code:
`
if index==1:
self.questions=list(Question.objects.all())
`
However it still does not work and I have some unexpected results. When I try to restart the quiz, I have the list filled up, and on the second step it suddenly gets emptied and I really cannot figure out what's going wrong.

The problem with your approach is that HTTP is stateless. Each request should have all the information required for the server to handle it. In other words the server should absolutely not keep any state. In your case, the questions list represents a state.
More details about HTTP and its statelessness:
Why is it said that "HTTP is a stateless protocol"?
Instead of keeping a list of your questions on the server side you should randomly pull a question at each request from the client.
How to pull a random record using Django's ORM?
To make sure that the same questions does not appear twice there are multiple possible solutions:
the client should send the ids of the seen questions (perhaps by get Query parameters) when asking for a new question.
the client stores a session_id and sends that to the server with every request. The server then stores in a table the mapping between a session id and the question that were displayed so far.
cookies might represent a solution as well, but I would say it's the most complicated out of the 3
Personally I would go with the first solution.

Users banned by my Telegram bot do not stay banned?

TL;DR: Methods listed in "Attempts" are not working as they should. Whenever I run those Python methods, they end up only kicking the user (or maybe banning them for at maximum 2-3 minutes), regardless if I include until_date or not. All group permissions are enabled and in BotFather both group privacy mode and "allow groups?" are disabled.
I am new to Stack Overflow, so I'm not sure if the formatting of my question is fine and if a lengthy description is preferable.
Context: I have a (private) Telegram group with a little bit over 700 users. There are two other admins and five bots (Rose, Group Help, Combot and two that I coded). In the past couple of weeks I have been facing issues with banning users through my own bot, while Rose and Group Help bots seem to be able to.
Issue: My bot limits the amount of entries (per user) to the group to avoid people lurking, or just raiding the group when I share an invitation link. Group help bot and Rose kick people out if they don't solve the captcha and present themselves in the first 5 minutes upon entering. I keep Combot to avoid letting known spammers in my group. The problem I'm facing is that whenever the ban is issued by my own bot, the user will simply be kicked out. I tried various methods to ban a user in my Python script, but nothing worked. I tried switching from python-telegram-bot to AIOgram, but it still doesn't work. I am not sure if it's caused by a conflict between bots (which wouldn't make much sense), wrong methods, or if it's a group/account-related problem. I tried my bot in a "test group" and it worked fine.
Screenshot of an example of the anomaly from the group logs channel: Since I can't embed pictures yet, here is the imgur link.
Part of the current (pseudo)code using AIOgram:
#dp.message_handler(content_types=["new_chat_members"])
async def newUser(message: types.Message):
for user in message.new_chat_members:
con = psycopg2.connect(...)
#[...SQL query fetching number of entries of a user...]
if "DB is empty":
#..Initialize..
else:
cur.execute(sql_script) #cur is the cursor
#Returns a list with at most one tuple, where the first instance is the number of entries
entries_list = cur.fetchall()
if len(entries_list) == 0 or None:
#Adds user to a table in Heroku DB and initializes entry = 1
insertUser(tablename, userid, 1)
await bot.send_message(channel_id, log_message)
con.close()
elif entries_list[0][0] < 2:
updateUserEntries(tablename, entries_list[0][0] + 1, userid)
await bot.send_message(channel_id, log_message)
con.close()
else: #Ban on third entry
await chat.kick(userid, until_date = datetime.now() + timedelta(hours = 6))
await bot.send_message(chat.id, ban_message)
await bot.send_message(channel_id, log_message)
#Removes user from the table (i.e. resets the entry count)
removeUser(tablename, userid)
con.close()
Attempts: The methods I tried using to ban users with are:
update.effective_chat.ban_member(chat_id, user_id) (python-telegram-bot),
bot.kick_chat_member(chat_id, user_id) (python-telegram-bot),
bot.ban_chat_member(chat_id, user_id) (python-telegram-bot – which suggested me to use kick_chat_member instead) and
message.chat.kick(user_id) (aiogram – where message is passed whenever a new user joins the group through Dispatcher.message_handler(content_types='new_chat_members')).
I originally only wanted to temporarily ban the users, so there should be an extra until_date parameter too. But I also tried permanently banning them, which according to the documentation any time less than 30 seconds or more than 366 days counts as a permanent ban. Nothing worked. (By the way, the script in general works and runs great. I am not sharing the full script because I am not comfortable with it being public, and the problem also does not pertain to the whole script anyways.)
Further details: My bot has all group permissions enabled except for adding admins and "remain anonymous". In BotFather it has both group privacy mode and "allow groups?" disabled (because I only use it for my group). At the moment the library I'm using for the bot (in Python) is AIOgram. Previously, it was all written using python-telegram-bot. I am using it in conjunction with psycopg2 to store user data in Heroku's database. At one point I even tried creating a "ban table" in my database, but it still failed to keep the users out since the ban didn't actually ban people. The ban actually only acts as a "kick".
I was thinking about setting up a webhook, but I am not familiar with Flask or Django, and webhooks in general. So that might take me some time. However, I'm not sure it would make a difference since it should not differ much, except maybe speed and memory wise.
I am not sure what I'm doing wrong. I tried to solve the problem in every way that I am capable of (considering that I am pretty new to Telegram API and Telegram python libraries, especially AIOgram).
If anyone has any ideas on how I can go about solving this issue, I would really appreciate it!
(Sidenote: I contacted Telegram support more than a week ago, but I haven't received any response.)

It's not obvious to me what goes wrong here, but I have a few hints/remarks:
which library you use to make the api request should be irrelevant. you can even make the request manually via the browser/curl/whatever if you like to
webhooks have nothing to do with this - how you fetch updates is indpendent of making requests to the api
python-telegram-bot interprets timezone-naive datetimes as UTC - that may have an effect how you pass the until_date
Dislaimer: I'm currently the maintainer of python-telegram-bot.

Thank you, #CallMeStag for your remarks! I ended up "solving" the problem as I describe below. Although, I am still not sure why this worked but using any of the methods I listed in the question didn't.
Disclaimer: This is not an efficient way to approach the issue, and I do not guarantee it will work. I also don't have a high traffic of people joining the group, so these solutions might not work for you.
Partial (non-)solutions: I think there is a "phantom issue" between my bot and Telegram. Somehow Telegram (or Python, I'm not sure) doesn't understand the "kick" methods as "ban", whether I include until_date or not. (Also, Telegram support is non-existent). So, I thought of three (or four) alternative ways to ban someone without having to actually ban them:
Solution 1: Create a table in your database that will contain all the users that you will eventually ban. For your "ban" function, include a message handler that listens for new chat members. Whenever a new user joins (use new_chat_members to catch the event), make it run through all the entries in the table you created (e.g. you could use SELECT COUNT(*) FROM {BANTABLENAME} WHERE USERID = {USERID}) so that it will tell you if the user is banned. If the query returns a value greater than 0, you can just make an IF statement and kick the user out. (You can obviously make it a bit more complicated by manually adding an until_date). The downside is that it can fail to keep a user out since there is a bit of latency/delay when you run SQL queries.
Solution 2: This solution still requires that you create a table of banned users in your database. But instead of letting people join your group directly, direct them to your bot's chat first. Add a command handler for "/start". Whenever a user starts the bot, make it run through the table entries and depending on the result, the bot will either reply with the group link or a message informing them that they can't join (or nothing).
Solution 3: Set up a webhook. I don't know how to do it yet, so you should look it up on the internet. It will require you to learn at least Flask, or Django. This is definitely a nicer solution compared to the other ones. Usually, this "ban problem" does not pertain to whether you're using a webhook or not (like CallMeStag said). But compared to my next proposal (which works somehow), this is definitely a better practice.
Solution 4 (Verified): I was curious and wanted a more direct solution, so I decided I would just try manually making requests through www.api.telegram.org/bot<TOKEN>/METHOD?PARAMETERS using GET and POST HTTPS methods in Python. This is definitely not an ideal solution if you have a high traffic of users. Because you might get errors due to too many requests. Also, depending on what you're trying to do, it might be too slow. So definitely use webhooks instead. In my case, I only need to POST the ban using the banChatMember method, which also happens with a pretty low frequency. So I should not encounter problems. (I will update if I do).
Further doubts: I am not sure why solution 4 works, but directly banning with python-telegram-bot or AIOgram doesn't. I did not try Telethon or Pyrogram. They should be similar, but they also allow you to log-in as a user (i.e. it will start a session of your account through the bot), which could potentially work.
Update: It doesn't work. Banned users still don't get banned. It only works when I manually do it for some reason. The whole thing really doesn't make any sense. It's like it doesn't work while polling, but it works if I manually send out www.api.telegram.org/bot<token>/banChatMember?chat_id=<chatid>&user_id=<userid>.

How to send different messages to users with different settings? discord.py

First of all, I'm a beginner at discord.py. It's hard to explain my problem but I'll try my best:
I'm trying to make a single command which sends different messages to users with different settings.
For example:
Let's say my bot has 2 commands !command and !settings.
A user changes his/her setting with the setting command: "!settings (setting1/setting2/setting3/setting4...)"
If the user uses the !command with (setting1), it will send "response1". But if user has (setting2) it will send "response2", and if user has (setting3) it will send "response3" and so on...
I will appreciate any help :)

I will try my best to explain to you!
To make it happen, we need to store those data in the database!(what is database? to store some data which we can update, delete, and use anytime.) So, we are going to store it in the database. (what we are going to store? we are going to store each user's settings)
For Example! if a person used !settings 1 then we are going to store it in database like this.
{ "user_id": discord_user_id_here,"settings":1}
the discord user id of each person is unique so we use that to store it in the database!.(but where we are going to store it? there is a free best company called "MongoDB" is providing us free database! we will save our data there. and we can completely control it with python)
Now we have saved that user in database and we can do anything in that! but now the important thing, after saved when he uses the first command "!command", we need to fetch the settings from the database! and we can run anything according to his settings!.
LINKS:
MongoDB - https://www.mongodb.com/
MongoDB python Docs - https://pymongo.readthedocs.io/en/stable/
Complete Best Tutorial For MongoDB python - https://www.youtube.com/watch?v=rE_bJl2GAY8

Do telegram chat IDs stay the same when converting to a supergroup?

On Telegram, every group has a chat-id that my bot saves whenever it is added to a group.
If an owner of a group converts it to a supergroup, will the ID of the group change? And if it does, how can we get the new chat-id for the group?
I've looked for this all over the internet without success, so I'm asking here to self-answer to help people looking for this in the future, saving them the time trial and error took me.

After testing it out for myself, the chat-id does change on migration to a supergroup.
However I found the following way, using python-telegram-bot to keep your chat-ids updated:
def migchat(bot, update):
oldchatid = update.message.migrate_from_chat_id
newchatid = update.message.chat.id
# process those values as needed (e.g. update a database)
dispatcher.add_handler(MessageHandler(Filters.status_update.migrate, migchat))
This uses the Filters submodule to call migchat whenever a chat is being migrated.
This is how the JSON response of the message from the /getUpdates call looks like:

Warning while saving opportunity in OpenERP

After creating an opportunity, when I click on save, it gives me this warning for some users:
"Operation prohibited by access rules, or performed on an already deleted document (Operation: read, Document type: User Modification)."
What's causing this problem?
Update: I have created a new user of admin type and I added these groups:
Sales/User,Sales/User All Leads,Survey/User,Tools/User. It gives me a warning while creating an opportunity.
I added the following groups to the new user and it's working fine: Employee, PartnerManager, Marketing/User, Accounting/Accountant, Accounting/Invoice, Accounting/Manager, Administration/Access Rights, Human Resource/Manager, Human Resource/User, Knowledge/User, Marketing/Manager, Project/Manager, Sales/Manager, Tools/Manager, trimax/AdminMeeting, Trimax/‌​SalesExecutive, Trimax/Vertical, Trimax/SalesHead, Trimax/SalesManager, Useability/An‌alyticAccounting, Useability/Extended, View, Useability/MultiCompanies, Useability/No One, Useability/Product Uos View, Useability/Product Variant, Warehouse/Manager, Warehouse/User, Tools/User, Administration/Configuration
But in already created user if I remove the above groups which give warning ,then also it shows same warning.
The solution I mentioned above was for new users,but for some existing users it was still giving problem. So I removed some unwanted groups, which I didn't needed for those users and it worked, now it does not show warning. Was the warning due to some access right overlap or something else?

Those users probably don't have access rights for the opportunity object, or some child object. Read the access rights documentation for more details.
Update: You said that you're having trouble configuring a new user. As an experiment, try adding permissions to an existing user instead of starting a brand new user. Also, check that you've configured the roles as well as the permissions, that trips me up sometimes.
Another Update: You said that removing some groups stopped the warning. It may be that you have removed all access rules from the object. If no groups are explicitly granted access to something in OpenERP, then everyone is granted access. If you really want to figure out what's going on, I suggest you read the documentation I linked to above. You can also search for the error message in the source code and see exactly what it is complaining about. I find it really helpful to run the OpenERP server in debug mode, and step through the code when I'm trying to understand some weird behaviour like this. You can also try and figure out exactly which change triggers this error by adding and removing groups until you find a single change that makes the problem happen.

Hi these is due to the access right problem .So you give the proper access right to your user(for creating the oppurtunity)

same problem here.I'm using Multi-company, I provid all permistion to the user