Question: In what region of Africa is the country where the  Tartit (meaning "union"), band from the Tombouctou Region were formed located?

Context paragraphs:
Gao Region: The Gao Region is located in northeastern Mali.  The capital city is Gao.  The region is bordered to the north by Kidal Region, to the west by Tombouctou Region, and to the east and most of the south by Niger, with a very small portion of the southern border shared with Burkina Faso.  Common ethnicities in the Gao Region include the Songhai, Bozo, Tuareg, Bambara, and Kounta.  The towns include Gao, Bourem, and Bamba.

Mauritania: Mauritania ( ; Arabic: موريتانيا‎ ‎ "Mūrītānyā "; Berber: or Agawej ; Wolof: "Gànnaar" ; Soninke: "Murutaane"; Pulaar: "Moritani"; French: "Mauritanie" ), officially the Islamic Republic of Mauritania, is a country in the Maghreb region of western Africa.  It is the eleventh largest country in Africa and is bordered by the Atlantic Ocean to the west, Western Sahara in the north, Algeria in the northeast, Mali in the east and southeast, and Senegal in the southwest.

Regions of Mali: Since 2016, Mali has been divided into ten regions and one capital district.  A reorganization of the country from eight to nineteen regions was passed into law in 2012, but of the new regions, only Taoudénit (formerly part of Tombouctou Region) and Ménaka (formerly Ménaka Cercle in Gao Region) have begun to be implemented.  Each of the regions bears the name of its capital.  The regions are divided into 56 cercles.  The cercles and the capital district are divided into 703 communes.

Timbuktu Cercle: Timbuktu Cercle is an administrative subdivision of the Tombouctou Region of Mali.  It is the largest cercle by area in the whole of Mali.  The capital lies at the city of Timbuktu.  The cercle is divided into Rural and Urban Communes, and below this, quarters/villages.  In the 2009 census the cercle had a population of 124,546.

Gargando: Gargando is a small town located in the Tombouctou Region of Mali.  The people are mainly from subdivisions of the Kel Ansar tribe (which traces its origin to the Ansar of Medina).  The village has a large number of educated Touareg people.

Goundam: Goundam is a commune and town in north central Mali, in the Tombouctou Region.  It is the capital of Goundam Cercle, one of five subdivisions of the Region.  In the 2009 census the commune had a population of 16,253.  The main ethnic groups are Songhay, Tuareg and Fulani.

Tartit: Tartit (meaning "union") are a band from the Tombouctou Region of Mali.  The group consists of five women and four men, all of whom are Tamasheq-speaking Tuareg.  They formed in 1992 in a refugee camp in Mauritania.  Imharhan, an expanded group that includes current and former Tartit members, incorporates electric instruments and cross-cultural experiments into their music.

Niafunké Airport: Niafunké Airport (ICAO: GANF) is an airport serving Niafunké, a town in the Niafunké Cercle in the Tombouctou Region of Mali.

Taoudénit Region: Taoudénit is a region of Mali legislatively created in 2012 from the northern part of Timbuktu Cercle in Tombouctou Region.  Actual implementation of the region began on 19 January 2016 with the appointment of Abdoulaye Alkadi as the region's governor.  Members of the region's transitional council were appointed on 14 October 2016.  The region is divided into six cercles: Achouratt, Al-Ourche, Araouane, Boudje-Béha, Foum-Alba and Taoudénit.  The capital will be located at Taoudénit, although the government is currently based in Timbuktu owing to the lack of infrastructure in Taoudénit.

Tombouctou Region: Tombouctou Region is one of the administrative regions of Mali.  It is the largest of Mali's eight regions and includes a large section of the Sahara Desert.  For administrative purposes, the region is subdivided into five cercles.

Supporting paragraphs: Tartit Mauritania
Answer: west