def METHOD_NAME(self, phone_number: str):
    """Validate phone number and send message"""
    stage: AuthenticatorSMSStage = self.executor.current_stage
    hashed_number = hash_phone_number(phone_number)
    query = Q(phone_number=hashed_number) | Q(phone_number=phone_number)
    if SMSDevice.objects.filter(query, stage=stage.pk).exists():
        raise ValidationError(_("Invalid phone number"))
    # No code yet, but we have a phone number, so send a verification message
    device: SMSDevice = self.request.session[SESSION_KEY_SMS_DEVICE]
    stage.send(device.token, device)