instruction: what was the last value of a ph lab test of patient 006-77873 in 11/last year?
response: SELECT lab.labresult FROM lab WHERE lab.patientunitstayid IN (SELECT patient.patientunitstayid FROM patient WHERE patient.patienthealthsystemstayid IN (SELECT patient.patienthealthsystemstayid FROM patient WHERE patient.uniquepid = '006-77873')) AND lab.labname = 'ph' AND DATETIME(lab.labresulttime, 'start of year') = DATETIME(CURRENT_TIME(), 'start of year', '-1 year') AND STRFTIME('%m', lab.labresulttime) = '11' ORDER BY lab.labresulttime DESC LIMIT 1