instruction: what was the name of the drug prescribed during the last hospital encounter to patient 002-56853 two times?
response: SELECT t1.drugname FROM (SELECT medication.drugname, COUNT(medication.drugstarttime) AS c1 FROM medication WHERE medication.patientunitstayid IN (SELECT patient.patientunitstayid FROM patient WHERE patient.patienthealthsystemstayid IN (SELECT patient.patienthealthsystemstayid FROM patient WHERE patient.uniquepid = '002-56853' AND NOT patient.hospitaldischargetime IS NULL ORDER BY patient.hospitaladmittime DESC LIMIT 1)) GROUP BY medication.drugname) AS t1 WHERE t1.c1 = 2