Updated models.py

Changed the model field of year_published to an integer field

agusyquia_reading/bookshelf/models.py

@@ -15,7 +15,7 @@ class Books(models.Model):
     title = models.CharField(max_length=100)
     author = models.ForeignKey(Author, on_delete=models.CASCADE)
     publisher = models.CharField(max_length=69)
-    year_published = models.DateField()
+    year_published = models.IntegerField(default=2000)
     ISBN = models.IntegerField(default=0)
     blurb = models.TextField(max_length=700)