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I am working on a UI where I am supposed to run a python script with a HTML button. I am using flask for it.

There are two "insight engine" buttons in my UI. One in navigation bar at top and another one is simple button in blue color with upload icon.

Below is the code:

1. for flask main.py

I am using Flask WTF to display the results of a database query, but I would like to change the color of the cell background to light red if the value is less than 25. I am not certain how and where to insert the javascript to test the cell value and change the CSS class for that data cell. At present I can change the whole column data to bootstrap class "bg-danger", but not one cell.

Here is a simplified version of the python code:

I started building my flask app with a very basic structure detailed here, basically everything in one directory. As I have added more dependencies to my project, the need to separate my app into individual components has come up. Here is a look at how I have everything organized right now:

I am very new to Flask. While performing query on a database, it throws the following error. Can you please help me to understand why the error is issued?

C:\Users\tamim\Documents\Python_projects\user_login_sql\launch.py:7: SyntaxWarning: 'NoneType' object is not callable; perhaps you missed a comma?

if User.query.filter_by(username='John').first() is None(): Traceback (most recent call last):

File "C:\Users\tamim\Documents\Python_projects\user_login_sql\launch.py", line 7, in if User.query.filter_by(username='John').first() is None(): TypeError: 'NoneType' object is not callable

I am trying to use SQLAlchemy with Flask instead of following Flask-SQLAlchemy. The module which is used to launch the app is below:

There are a lot of questions regarding this but none of them are using Flask Blueprints.

I am trying to set up a QuerySelectField with a sqlite3 lookup. But I get then error:

I am working in flask through windows, and I am also using BackgroundScheduler. What I intend to do is to start the backgroundscheduler by clicking a button, afterwards, I would like to see a value increasing according to the time interval that I am specifying. The problem that I am currently having is that I need to press the start button multiple times to see the updated value.

I have the following code:

My simplified flask app:

Everything was working fine, the imports have always worked and my project structure has not changed. I made some changes - adding fields & forms, and suddenly all the relative imports in my app/main/views.py stopped working. I reverted my changes - that did not work either. Help!

Update: So it runs fine from the command line with "flask run", but not in PyCharm. So I'm thinking it's PyCharm config issue. My config.py file has not changed at all, so I think it's here: PyCharm Run/Debug Config

I did not intentionally make ANY changes to the config.... so not sure what the next step is here. If anyone has advice on the config for this project, I would be grateful!

Here's the project structure. App, Auth and Main are shown as packages: Project Structure

Here's the main app demo.py:

I followed a Flask tutorial and I am wanting to use error handling 404 and 500 to display custom webpages. I created 404.html and 500.html within the static/templates folder.

When I try to enter a wrong url such as 'http://127.0.0.1:5000/wfefef', I just get a blank page and a console error: 127.0.0.1 - - [09/Jul/2021 14:35:12] "GET /wfefef HTTP/1.1" 404 instead of giving me the custom html pages to handle such errors. What am I doing wrong?

Folder structure image: -

The code for app.py is as follows:

I am building a Flask app and following Miguel Grinberg's excellent tutorial/book. I am trying to have a separate worker process execute some tasks. When I include the create_app function in the tasks file at the top of the script as per the structure below I get the error message: