No. EMUs may manage because of high gear ratios and distributed traction. But a locomotive system won't work there, or will be highly inefficient. I'll be surprised if someone says "A WAP7 can balance a 24-coach train on a 1:20 grade". :P
For such grades, MG or NG would be fine. In Nilgiri Hills, where the ruling gradient is 1:12.5, rack and pinion system is used.