code: def test_plain_conn(db):
      """Manipulate database by `conn.query` without transactions."""
      conn = db.get_connection()
      conn.query("INSERT INTO foo VALUES (42)")
      conn.query("INSERT INTO foo VALUES (43)")
      assert conn.query("SELECT count(*) AS n FROM foo")[0].n == 2
  
imports: import pytest
label_desc: Use image node_id 2 for calling a global function with example usage: test_plain_conn(db) without return types