If all the bonds or warrants secured by assessments in any special assessment district in a municipality have been paid off and retired, and there are any special assessment, assessments or installments thereof remaining in the special assessment district which have not been paid off or discharged, then the governing body, in its discretion, may compromise and discharge the assessment, assessments or installments thereof, including penalties, for such sum as the governing body determines to be in the best interest of the municipality.
Okla. Stat. tit. 11, § 36-120