Write SQL query to solve given problem: How many customers are from Australia?. Keep the solution inside sql tag ```sql [SQL-Query] ```
SELECT COUNT(*) FROM customer_address AS T1 INNER JOIN address AS T2 ON T2.address_id = T1.address_id INNER JOIN country AS T3 ON T3.country_id = T2.country_id WHERE T3.country_name = 'Australia'