May a utility company refuse to provide service to a debtor if the company's utility bill is discharged under chapter 7?

If, within 20 days after a chapter 7 case is filed, the debtor furnishes a utility company with a deposit or other security to insure the payment of future utility services, it is illegal for a utility company to refuse to provide future utility service to the debtor, or to otherwise discriminate against the debtor, if its bill for past utility services is discharged in the chapter 7 case.