What are the students ids of students who have more than one allergy?
SELECT StuID FROM Has_allergy GROUP BY StuID HAVING count(*)  >=  2
SELECT StuID FROM Has_allergy GROUP BY StuID HAVING count(*)  >=  2
[{'StuID': 1002}, {'StuID': 1005}, {'StuID': 1007}, {'StuID': 1010}, {'StuID': 1015}, {'StuID': 1016}, {'StuID': 1018}, {'StuID': 1022}, {'StuID': 1023}, {'StuID': 1024}, {'StuID': 1029}, {'StuID': 1031}]