Using the table playground.messenger, write a SQL query to find the number of unique conversation threads in the playground.messenger table. A conversation thread is identified by the sender_id and receiver_id columns. Note that if a thread has sender_id and receiver_id inverted in another row, it should still be counted as the same thread. For example, a conversation where sender_id=1 and receiver_id=2 should be considered the same thread as one where sender_id=2 and receiver_id=1. The result should just be a single column called count given in any order.

• sender_id int
• receiver_id int

SELECT * FROM playground.messenger LIMIT 100