data of 15 on each model has been populated

bookshelf/migrations/0001_initial.py

+# Generated by Django 4.1.7 on 2023-03-27 11:54
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    initial = True
+
+    dependencies = [
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='Author',
+            fields=[
+                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('first_name', models.CharField(max_length=50)),
+                ('last_name', models.CharField(max_length=500)),
+                ('age', models.IntegerField()),
+                ('nationality', models.CharField(max_length=70)),
+                ('bio', models.CharField(max_length=700)),
+            ],
+        ),
+        migrations.CreateModel(
+            name='Books',
+            fields=[
+                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('title', models.CharField(max_length=100)),
+                ('publisher', models.CharField(max_length=100)),
+                ('year_published', models.DateTimeField(verbose_name='date published')),
+                ('ISBN', models.CharField(max_length=13)),
+                ('blurb', models.CharField(max_length=250)),
+                ('author', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, to='bookshelf.author')),
+            ],
+        ),
+    ]

bookshelf/models.py

@@ -11,7 +11,7 @@ class Author(models.Model):
 
     # important in visualizing 
     def __str__(self):
-        return self.first_name, self.last_name
+        return self.first_name + " " + self.last_name
 
 
 # Books model
@@ -25,5 +25,5 @@ class Books(models.Model):
     
 
     def __str__(self):
-        return self.title, self.publisher
+        return self.title + " " + self.publisher