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Let me point out that losing migration files is a very bad situation and should be avoided at all costs, but if it happens, having a step-by-step way to preserve the database is a good thing to have. It is a terrible situation to be in if your database/models/migrations are a shared state across multiple team members, and that would require a coordinated halt and cleanup so everyone can move forward from the same base state again, with a proper migration files workflow from then on.

Let's assume you have models, any number of migration files, all of those applied to your existing database. Now for some reason, poof!, all the migration files are gone.

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Partially ignore table fields on a Django model

There may come a day where your table includes a field that your Django app should ignore and not even be aware of, while other clients may still need to use that field in production through normal SQL commands. How to achieve this?

Removing a model field will give you a migration step like this:

        migrations.RemoveField(
 model_name="mymodel",

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import subprocess

def add_progressbar_on_top_of_video(
    input_video_filepath: str,
    output_video_filepath: str,
    width: int,
    height: int,
    duration: float,
    fps: float = 25.0,
    progressbar_height: int = 8,

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class Bar:
    def __init__(self):
        self.parent_class_attr_name = None


class LetClassAttributesKnowTheirName(type):
    def __new__(mcs, name, bases, attributes):
        for attr_name, attr_value in attributes.items():
            if isinstance(attr_value, Bar):
                attr_value.parent_class_attr_name = attr_name

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{% extends "admin/base_site.html" %}

{% block usertools %}
  {% url 'admin:index' as admin_index_url %}
  {% if request.get_full_path == admin_index_url %}
    <input
      type="text"
      id="admin_base_search"
      placeholder="Search..."
      autofocus

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Google Chrome Launch Argument Order may matter

--disable-web-security VS --user-data-dir

Also see: https://peter.sh/experiments/chromium-command-line-switches/#disable-web-security

I came across an issue with running google-chrome to render some HTML file, where we are loading fonts from an external URL and to avoid CORS screaming at us we configured it like:

google-chrome --user-data-dir=/tmp/ --disable-web-security

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# Update: Turns out there is a specific tool for this kind of migration that should
#   do a better job as my multistep-migration below, check out SeparateDatabaseAndState:
#
#   https://docs.djangoproject.com/en/5.0/howto/writing-migrations/#changing-a-manytomanyfield-to-use-a-through-model

# Changing the through= part of a models.ManyToManyField() fails to migrate, 
# as Django won't let us do this in a single step. We can manually workaround 
# with several migration steps though, as shown below.
#
# Based on Django 3.2

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# Django's models.FileField stores FieldFile objects. These have both .name 
# and .path attributes, which however are not exactly intuitive:

my_instance.my_filefield.name 
# E.g. whatever/123/foo.png
# Returns the path relative to MEDIA_ROOT, not the filename!
# For the filename do e.g. os.path.basename(my_instance.my_filefield.name)

my_instance.my_filefield.path
# E.g. /var/www/media/whatever/123/foo.png

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# https://pypi.org/project/memory-profiler/
pip install -U memory_profiler

mprof run --include-children --attach <pid>
mprof plot

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"""A script to help update many querycount assertions in code quickly.

Requirements:

    pip install redbaron

Deprecation note:

    redbaron (based on baron) is somewhat unmaintained and only supports
    Python grammar u to version 3.7, so for newer Python versions we may