<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def send_alert_to_subscribed_integrations(alert):
 """Send Alert to relevant integrations."""

    valid_configured_integrations = get_valid_configured_integrations(alert)

    for configured_integration in valid_configured_integrations:
        threading.Thread(target=create_integration_alert_and_call_send, args=(alert, configured_integration)).start()