Add migration file

InvenTree/stock/migrations/0074_alter_stockitem_batch.py

@@ -0,0 +1,19 @@
+# Generated by Django 3.2.12 on 2022-04-26 10:19
+
+from django.db import migrations, models
+import stock.models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('stock', '0073_alter_stockitem_belongs_to'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='stockitem',
+            name='batch',
+            field=models.CharField(blank=True, default=stock.models.generate_batch_code, help_text='Batch code for this stock item', max_length=100, null=True, verbose_name='Batch Code'),
+        ),
+    ]

InvenTree/stock/models.py

@@ -227,6 +227,8 @@ def generate_batch_code():
 
     now = datetime.now()
 
+    # Pass context data through to the template randering.
+    # The folowing context variables are availble for custom batch code generation
     context = {
         'date': now,
         'year': now.year,