Merge pull request 'master' (#116) from master into 110_Biotope_codelists

Reviewed-on: SGD-Nord/konova#116

codelist/models.py

@@ -65,6 +65,26 @@ class KonovaCode(models.Model):
             ret_val += ", " + self.parent.long_name
         return ret_val
 
+    def add_children(self):
+        """ Adds all children (resurcively until leaf) as .children to the KonovaCode
+
+        Returns:
+            code (KonovaCode): The manipulated KonovaCode instance
+        """
+        if self.is_leaf:
+            return None
+
+        children = KonovaCode.objects.filter(
+            code_lists__in=self.code_lists.all(),
+            parent=self
+        ).order_by(
+            "long_name"
+        )
+        self.children = children
+        for child in children:
+            child.add_children()
+        return self
+
 
 class KonovaCodeList(models.Model):
     """