title: Disable unique constraint on Django's ManyToManyField
body: <p>From <a href="https://docs.djangoproject.com/en/3.1/ref/models/fields/#django.db.models.ManyToManyField.through" rel="nofollow noreferrer">the Django documentation</a> for <a href="https://docs.djangoproject.com/en/3.1/ref/models/fields/#manytomanyfield" rel="nofollow noreferrer"><code>ManyToManyField</code></a>:</p>
  <blockquote>
  <p>If you don’t want multiple associations between the same instances, add a UniqueConstraint including the from and to fields. Django’s automatically generated many-to-many tables include such a constraint.</p>
  </blockquote>
  <p>How do I disable this constraint? Is the only way to provide an explicit <code>through</code> table? Or is there a way to tell Django to not add the <code>UniqueConstraint</code> to the generated many-to-many-table?</p>