Tweak base BatchRowCrud view class, for fieldset customization.

tailbone/views/batch.py

@@ -1020,6 +1020,22 @@ class BatchRowCrud(BaseCrud):
         """
         return self.batch_class.__name__
 
+    def fieldset(self, row):
+        """
+        Creates the fieldset for the view.  Derived classes should *not*
+        override this, but :meth:`configure_fieldset()` instead.
+        """
+        fs = self.make_fieldset(row)
+        self.configure_fieldset(fs)
+        return fs
+
+    def configure_fieldset(self, fieldset):
+        """
+        Derived classes can override this.  Customizes a fieldset which has
+        already been created with defaults by the base class.
+        """
+        fieldset.configure()
+
     def template_kwargs(self, form):
         """
         Add batch row instance etc. to template context.