[Django]-Django error message "Add a related_name argument to the definition"

Example:

class Article(models.Model):
    author = models.ForeignKey('accounts.User')
    editor = models.ForeignKey('accounts.User')
    

This will cause the error, because Django tries to automatically create a backwards relation for instances of accounts.User for each foreign key relation to user like user.article_set. This default method is ambiguous. Would user.article_set.all() refer to the user’s articles related by the author field, or by the editor field?

Solution:

class Article(models.Model):
    author = models.ForeignKey('accounts.User', related_name='author_article_set')
    editor = models.ForeignKey('accounts.User', related_name='editor_article_set')

Now, for an instance of user user, there are two different manager methods:

1. user.author_article_set — user.author_article_set.all() will return a Queryset of all Article objects that have author == user

2. user.editor_article_set — user.editor_article_set.all() will return a Queryset of all Article objects that have editor == user

Note:
This is an old example — on_delete is now another required argument to models.ForeignKey. Details at What does on_delete do on Django models?

“If a model has a ForeignKey, instances of the foreign-key model will have access to a Manager that returns all instances of the first model. By default, this Manager is named FOO_set, where FOO is the source model name, lowercased.”

But if you have more than one foreign key in a model, django is unable to generate unique names for foreign-key manager.
You can help out by adding “related_name” arguments to the foreignkey field definitions in your models.

See here:
https://docs.djangoproject.com/en/dev/topics/db/queries/#following-relationships-backward

If your models are inheriting from the same parent model, you should set a unique related_name in the parent’s ForeignKey. For example:

author = models.ForeignKey('accounts.User', related_name='%(app_label)s_%(class)s_related')

It’s better explained in the docs

If your models are inheriting from the same parent model, you should set a unique related_name in the parent’s ForeignKey. For example:

author = models.ForeignKey('accounts.User', related_name='%(app_label)s_%(class)s_related')

It’s better explained in th

I had a similar problem when I was trying to code a solution for a table that would pull names of football teams from the same table.
My table looked like this:

hometeamID = models.ForeignKey(Team, null=False, on_delete=models.CASCADE)
awayteamID = models.ForeignKey(Team, null=False, on_delete=models.CASCADE)

making the below changes solved my issue:

hometeamID = models.ForeignKey(Team, null=False, on_delete=models.CASCADE,related_name='home_team')
awayteamID = models.ForeignKey(Team, null=False, on_delete=models.CASCADE,related_name='away_team')

But in my case i am create a separate app for some functionality with same model name and field ( copy/paste ) that’s because of this type of error occurs i am just deleted the old model and code will work fine
May be help full for beginners like me

This isn’t an ultimate answer for the question, however for someone it may solve the problem.
I got the same error in my project after checking out a really old commit (going to detached head state) and then getting the code base back up to date. Solution was to delete all *.pyc files in the project.

Do as the error message instructs you to:

Add a related_name argument to the
definition for ‘creator’.