add last fm similar artists to db table

+ add db methods for the above
+ try and discard last fm store

app/db/sqlite/lastfm/similar_artists.py

@@ -0,0 +1,62 @@
+from app.models.lastfm import SimilarArtist
+
+from ..utils import SQLiteManager
+
+
+class SQLiteLastFMSimilarArtists:
+    """
+    This class contains methods for interacting with the lastfm_similar_artists table.
+    """
+
+    @classmethod
+    def insert_one(cls, artist: SimilarArtist):
+        """
+        Inserts a single artist into the database.
+        """
+        sql = """INSERT OR REPLACE INTO lastfm_similar_artists(artisthash, similar_artists) VALUES(?,?)"""
+
+        with SQLiteManager(userdata_db=True) as cur:
+            cur.execute(sql, (artist.artisthash, artist.similar_artist_hashes))
+            cur.close()
+
+    @classmethod
+    def get_similar_artists_for(cls, artisthash: str):
+        """
+        Returns a list of similar artists.
+        """
+        sql = """SELECT * FROM lastfm_similar_artists WHERE artisthash = ?"""
+        with SQLiteManager(userdata_db=True) as cur:
+            cur.execute(sql, (artisthash,))
+            similar_artists = cur.fetchone()
+            cur.close()
+
+            if similar_artists is None:
+                return None
+
+            return SimilarArtist(artisthash, similar_artists[2])
+
+    @classmethod
+    def get_all(cls):
+        """
+        Returns a list of all similar artists.
+        """
+        sql = """SELECT * FROM lastfm_similar_artists"""
+        with SQLiteManager(userdata_db=True) as cur:
+            cur.execute(sql)
+            similar_artists = cur.fetchall()
+            cur.close()
+
+            for a in similar_artists:
+                yield SimilarArtist(a[1], a[2])
+
+    @classmethod
+    def exists(cls, artisthash: str):
+        """
+        Checks if an artist exists in the database by counting the number of rows
+        """
+        sql = """SELECT COUNT(*) FROM lastfm_similar_artists WHERE artisthash = ?"""
+        with SQLiteManager(userdata_db=True) as cur:
+            cur.execute(sql, (artisthash,))
+            count = cur.fetchone()[0]
+            cur.close()
+            return count > 0