added client RA bill wise download report

app/services/db_service.py

@@ -0,0 +1,19 @@
+from flask_sqlalchemy import SQLAlchemy
+from flask_migrate import Migrate
+
+db = SQLAlchemy()
+migrate = Migrate()
+
+
+# import mysql.connector
+# from app.config import Config
+
+# class DBService:
+
+#     def connect(self):
+#         return mysql.connector.connect(
+#             host=Config.DB_HOST,
+#             user=Config.DB_USER,
+#             password=Config.DB_PASSWORD,
+#             database=Config.DB_NAME
+#         )