when patient 67902 had the first closed bronchial biopsy until 2100?
select procedures_icd.charttime from procedures_icd where procedures_icd.icd9_code = ( select d_icd_procedures.icd9_code from d_icd_procedures where d_icd_procedures.short_title = 'closed bronchial biopsy' ) and procedures_icd.hadm_id in ( select admissions.hadm_id from admissions where admissions.subject_id = 67902 ) and strftime('%y',procedures_icd.charttime) <= '2100' order by procedures_icd.charttime asc limit 1