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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def send_password_changed_notice(user):
 """Sends the password changed notice email for the specified user. :param user: The user to send the notice to """

    if config_value('SEND_PASSWORD_CHANGE_EMAIL'):
        subject = config_value('EMAIL_SUBJECT_PASSWORD_CHANGE_NOTICE')
        _security.send_mail(subject, user.email, 'change_notice', user=user)