; and (B) a parolee who is an addict (as defined under section 102 of the Controlled Substances Act ( 21 U.S.C. 802 )) or a drug dependent person (as defined in section 2 of the Public Health Service Act ( 42 U.S.C. 201 )) to undergo available medical, psychiatric, or psychological treatment for drug or alcohol dependency for all or part of the period of parole. (2) Costs A parolee residing in a residential community treatment center pursuant to paragraph (1) may be required to pay such costs incident to residence as the Commission determines appropriate. (d) Modification of conditions (1) In general The Commission may modify conditions of parole under this section on its own motion, or on the motion of a United States probation officer supervising a parolee. (2) Notice required A parolee shall receive notice of a proposed modification of conditions of parol and a period of not less than 10 days after receipt of such notice to express the views of the parolee on the proposed modification. (3) Period for determination Not later than 21 days after the end of the 10-day period described in paragraph (2), the Commission shall act upon a motion or application to modify conditions of parole. (4) Petition by parolee A parolee may petition the Commission for a modification of conditions under this section. (5) Relation to revocation proceedings This subsection shall not apply to modifications of parole conditions under a revocation proceeding under section 3643. 3639. Jurisdiction of Commission (a) Attorney General jurisdiction A parolee shall remain in the legal custody and under the control of the Attorney General, until the expiration of the maximum term or terms of imprisonment to which such parolee was sentenced. (b) Jurisdiction of Commission generally Except as otherwise provided in this section, the jurisdiction of the Commission over the parolee shall terminate not later than the date of the expiration of the maximum term or terms for which the parolee was sentenced, except that— (1) such jurisdiction shall