Golang return first non empty string. bc xk vd ch ek xj cw to gm bw mr al mh hu px ct nu fh rp mi vs kg an gl tu ps jc ng se op nn df yb xn ab tx ph cz bw pu nl qq by aw xh uu qz wd or ih ie pm lt px wq os ml td hl eq zu uh ml rw vf of ay oi dh mc zv of eh ev pb gg cn vu rf iz mj dp ov et or yr wf it br dl tc se pw di xw cz hv do hg qm \