[mercari Summer Internship 2017 Qualification] remove unused import
[mercari Summer Internship 2017 Qualification] remove unused import

mikoim/funstuff,mikoim/funstuff,mikoim/funstuff,mikoim/funstuff,mikoim/funstuff,mikoim/funstuff,mikoim/funstuff,mikoim/funstuff,mikoim/funstuff