adding docstring to classes

app/utils/database.py

@@ -1,14 +1,12 @@
 # utils/database.py
-"""Database utilities ....
+"""Database utilities for database operations.
 
-This module provides classes and functions for:
+This module provides utility functions and classes to interact with a database using SQLAlchemy. It includes:
-- ....
+- Creating a database engine with connection pooling.
-- ....
+- Generating a session factory for creating sessions.
-- ....
 """
 
 import logging
-
 from sqlalchemy import create_engine
 from sqlalchemy.orm import sessionmaker
 from sqlalchemy.pool import QueuePool
@@ -17,14 +15,21 @@ logger = logging.getLogger(__name__)
 
 
 def get_db_engine(database_url: str):
-    """Create database engine with connection pooling."""
+    """Create a database engine with connection pooling.
+
+    Args:
+        database_url (str): The URL string to connect to the database. It can be for SQLite or PostgreSQL databases.
+
+    Returns:
+        sqlalchemy.engine.Engine: A SQLAlchemy Engine instance configured according to the provided database URL.
+    """
     if database_url.startswith("sqlite"):
-        # SQLite configuration
+        # Configuration for SQLite database
         engine = create_engine(
             database_url, connect_args={"check_same_thread": False}, echo=False
         )
     else:
-        # PostgreSQL configuration with connection pooling
+        # Configuration for PostgreSQL databases with connection pooling
         engine = create_engine(
             database_url,
             poolclass=QueuePool,
@@ -39,5 +44,12 @@ def get_db_engine(database_url: str):
 
 
 def get_session_local(engine):
-    """Create session factory."""
+    """Create a session factory to generate database sessions.
+
+    Args:
+        engine (sqlalchemy.engine.Engine): The SQLAlchemy Engine instance created by `get_db_engine`.
+
+    Returns:
+        sqlalchemy.orm.sessionmaker: A session factory bound to the provided engine, suitable for creating database sessions.
+    """
     return sessionmaker(autocommit=False, autoflush=False, bind=engine)