Use a context manager to write to /dev/null

django_migration_linter/migration_linter.py

@@ -302,8 +302,8 @@ class MigrationLinter:
 
     def get_sql(self, app_label, migration_name):
         logger.info(f"Calling sqlmigrate command {app_label} {migration_name}")
-        dev_null = open(os.devnull, "w")
         try:
+            with open(os.devnull, "w") as dev_null:
                 sql_statement = call_command(
                     "sqlmigrate",
                     app_label,