With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Steffi Graf was ranked the No.1 tennis player in the world during her career.
text_B: Columbina Rural. Service Center is a populated place in Zhombe .. Zhombe. Zhombe. It is 95km northwest of Kwekwe and 67km southwest of Kadoma .. Kwekwe. Kwekwe District. Kwekwe. Kwekwe. Kadoma. Kadoma, Zimbabwe. The Center is near the now. defunct Empress Nickel Mine. which is about 4 km to the. South-west .. Blue Gum mine is on the Gokwe side of Ngondoma River yet this place was the original Blue Gum according to all maps before 1980 .. Blue Gum was right at the. Samambwa Zhombe East Road turn-off here at Columbina RSC .. Zhombe. Zhombe. Search engines always point to this. place as Blue Gum , Zimbabwe .. Columbina Rural Service Center is in Mahogo Village ,
not_related.