How to efficiently use the Python `contextlib` module for resource management without causing memory leaks?
This might be a silly question, but I'm stuck on something that should probably be simple. I've been struggling with this for a few days now and could really use some help. I'm stuck on something that should probably be simple. I'm currently working on a data processing application using Python 3.10 and I've been trying to implement some resource management using the `contextlib` module. Specifically, I want to ensure that my database connections are properly closed after use to avoid memory leaks. However, I'm encountering some unexpected behavior where the context manager doesn't seem to release the resources as I expected. Here’s a simplified version of what I’ve implemented: ```python import contextlib import sqlite3 @contextlib.contextmanager def get_db_connection(db_name): conn = sqlite3.connect(db_name) try: yield conn finally: print("Closing connection...") conn.close() def process_data(): with get_db_connection('my_database.db') as conn: cursor = conn.cursor() cursor.execute('SELECT * FROM my_table') data = cursor.fetchall() print(data) # Assume some processing happens here if __name__ == '__main__': process_data() ``` I expected the connection to be closed after exiting the `with` block, but when I run this code multiple times in a loop, I see an increasing number of open connections in the SQLite database. The output shows 'Closing connection...' each time, but if I check the state of the database connections using an SQLite tool, it indicates that connections are still lingering. I've also tried using the `close()` method directly after the `yield` statement, but the behavior remains unchanged. Could it be that something is retaining a reference to the connection, or am I missing an important detail in how Python's context managers work? Any insights into best practices for using `contextlib` for resource management would be greatly appreciated! What am I doing wrong? My development environment is Windows 11. Thanks for taking the time to read this! What are your experiences with this?