'if field.many_to_many and field.remote_field.through._meta.auto_created: AttributeError: 'str' object has no attribute '_meta'

A source Django 3 by examples Chapter 14

When I try to run python manage.py migrate --settings=educa.settings.pro

Another files are copies and pastes from the book

The result is

  File "C:\Python\educa\manage.py", line 22, in <module>
    main()
  File "C:\Python\educa\manage.py", line 18, in main
    execute_from_command_line(sys.argv)
  File "C:\Users\DELL\AppData\Local\Programs\Python\Python39\lib\site-packages\django\core\management\__init__.py", line 419, in execute_from_command_line
    utility.execute()
  File "C:\Users\DELL\AppData\Local\Programs\Python\Python39\lib\site-packages\django\core\management\__init__.py", line 413, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "C:\Users\DELL\AppData\Local\Programs\Python\Python39\lib\site-packages\django\core\management\base.py", line 354, in run_from_argv
    self.execute(*args, **cmd_options)
  File "C:\Users\DELL\AppData\Local\Programs\Python\Python39\lib\site-packages\django\core\management\base.py", line 398, in execute
    output = self.handle(*args, **options)
  File "C:\Users\DELL\AppData\Local\Programs\Python\Python39\lib\site-packages\django\core\management\base.py", line 89, in wrapped
    res = handle_func(*args, **kwargs)
  File "C:\Users\DELL\AppData\Local\Programs\Python\Python39\lib\site-packages\django\core\management\commands\migrate.py", line 244, in handle
    post_migrate_state = executor.migrate(
  File "C:\Users\DELL\AppData\Local\Programs\Python\Python39\lib\site-packages\django\db\migrations\executor.py", line 117, in migrate
    state = self._migrate_all_forwards(state, plan, full_plan, fake=fake, fake_initial=fake_initial)
  File "C:\Users\DELL\AppData\Local\Programs\Python\Python39\lib\site-packages\django\db\migrations\executor.py", line 147, in _migrate_all_forwards
    state = self.apply_migration(state, migration, fake=fake, fake_initial=fake_initial)
  File "C:\Users\DELL\AppData\Local\Programs\Python\Python39\lib\site-packages\django\db\migrations\executor.py", line 227, in apply_migration
    state = migration.apply(state, schema_editor)
  File "C:\Users\DELL\AppData\Local\Programs\Python\Python39\lib\site-packages\django\db\migrations\migration.py", line 126, in apply
    operation.database_forwards(self.app_label, schema_editor, old_state, project_state)
  File "C:\Users\DELL\AppData\Local\Programs\Python\Python39\lib\site-packages\django\db\migrations\operations\fields.py", line 104, in database_forwards
    schema_editor.add_field(
  File "C:\Users\DELL\AppData\Local\Programs\Python\Python39\lib\site-packages\django\db\backends\base\schema.py", line 487, in add_field
    if field.many_to_many and field.remote_field.through._meta.auto_created:
AttributeError: 'str' object has no attribute '_meta'

Migration file:

from django.conf import settings
from django.db import migrations, models
import django.db.models.deletion

class Migration(migrations.Migration):

    dependencies = [
        migrations.swappable_dependency(settings.AUTH_USER_MODEL),
        ('account', '0005_contant'),
    ]

    operations = [
        migrations.CreateModel(
            name='Contact',
            fields=[
                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=True, verbose_name='ID')),
                ('user_from', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='rel_from_set', to=settings.AUTH_USER_MODEL)),
                ('user_to', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='rel_to_set', to=settings.AUTH_USER_MODEL)),
                ('created', models.DateTimeField(auto_now_add=True, db_index=True)),
            ],
            options={
                'ordering': ('-created',),
            },
        ),
    ]

Please help me, I don't know what to do.

Solution 1:^[1]

If you provide the code for your models.py file, that would help. However, a good reason for this type of error is when you're creating a through table for a many to many join and the through model has no __str__ method in it's Meta class. If the method exists check that the indentation is correct.

Sources

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Source: Stack Overflow

Solution	Source
Solution 1	Yemi Adeoye

'if field.many_to_many and field.remote_field.through._meta.auto_created: AttributeError: 'str' object has no attribute '_meta'

Solution 1:[1]

Sources

Related Questions

Solution 1:^[1]