Fixed #23282 -- Corrected inheritance and reverse relations example.

default :attr:`~django.db.models.ForeignKey.related_name` value for

:class:`~django.db.models.ForeignKey` and

:class:`~django.db.models.ManyToManyField` relations.  If you

are putting those types of relations on a subclass of another model,

you **must** specify the

:attr:`~django.db.models.ForeignKey.related_name` attribute on each

such field. If you forget, Django will raise an error when you run

:djadmin:`check` or :djadmin:`migrate`.

are putting those types of relations on a subclass of the parent model, you

**must** specify the :attr:`~django.db.models.ForeignKey.related_name`

attribute on each such field. If you forget, Django will raise a validation

error.

For example, using the above ``Place`` class again, let's create another

subclass with a :class:`~django.db.models.ManyToManyField`::

    class Supplier(Place):

        # Must specify related_name on all relations.

        customers = models.ManyToManyField(Restaurant, related_name='provider')

        customers = models.ManyToManyField(Place)

This results in the error::

    Reverse query name for 'Supplier.customers' clashes with reverse query

    name for 'Supplier.place_ptr'.

    HINT: Add or change a related_name argument to the definition for

    'Supplier.customers' or 'Supplier.place_ptr'.

Adding ``related_name`` to the ``customers`` field as follows would resolve the

error: ``models.ManyToManyField(Place, related_name='provider')``.

Specifying the parent link field

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