If I understand you it would be something along the lines of
## using you pseudo-code Select ACCT_ID, ZIP_CODE from a recs_a=cur_a.fetchall() select ALT_ID from b recs_b=cur_b.fetchall() combined_list=[] for ctr, row in enumerate(recs_a): ## assumes a and b are the same length combined_list.append([row[0], recs_b[ctr], row[1]])