made models: artist, album, and song under homepage

homepage/models.py

 from django.db import models
 
-# Create your models here.
+# for artists
+class Artist(models.Model):
+    artist_name = models.CharField(max_length = 50)
+    monthly_listeners = models.IntegerField()
+
+# for albums
+class Album(models.Model):
+    album_name = models.CharField(max_length = 100)
+    artist = models.CharField(max_length = 50)
+    description = models.CharField(max_length = 150)
+    release_date = models.DateTimeField("date published")
+
+# for songs
+class Song(models.Model):
+    song_title =  models.CharField(max_length = 100)
+    artist = models.CharField(max_length = 50)
+    album = models.ForeignKey(Album, on_delete = models.CASCADE)
+    song_length = models.IntegerField()
\ No newline at end of file