If you want to reuse a form template for e.g. creating and updating a model instance, there is a trick to specify the action:
Instead of
<form method="post" action="{% url 'cheeses:add' %}">
<!-- and -->
<form method="post" action="{% url 'cheeses:edit' %}">
you can use
<form method="post" action=".">
Using action="."
as is a commonly-used trick to reuse a form template for both create and update views.