Question: Viktor Zholudev commanded a division during its defense of a tractor factory located in a city now know as what

Context paragraphs:
S-65 Stalinets: The S-65 tractor or Stalinets S-65 was a very popular agricultural tractor built by the Chelyabinsk Tractor Factory ("Chelyabinskii Traktornyi Zavod" – "ChTZ") from 1937 until 1941.  These tractors were used in military service as they were widely available and capable of towing heavy guns.

KhTZ-16: The KhTZ-16 (Russian: "ХТЗ-16" ) (after the Kharkiv Tractor Factory; ) was a Soviet improvised armoured vehicle of the Second World War, built on the chassis of an STZ-3 tractor.  The vehicles were built in Kharkiv until the factory was evacuated to the east, at which time production moved to Stalingrad.  No less than 809 vehicles were planned, but no more than about 60 were actually built.  Some vehicles were used in the fighting around Kharkiv in October 1941, but were quickly lost.

37th Guards Rifle Division: The division was formed on 2 August 1942 from the 1st Airborne Corps in Lyubertsy, near Moscow.  Its most famous action was the defense of the Stalingrad Tractor Factory during the Battle of Stalingrad.  The division was highly decorated, receiving two Orders of the Red Banner, the Order of Suvorov 1st class, the Order of Kutuzov 1st class and the Order of Bogdan Khmelnitsky.  It became the 27th Guards Mechanised Division in December 1945 and on 20 April 1957 the 39th Guards Tank Division at Polotsk (Borovukha), Vitebsk Oblast, Belarussian Military District.  On 1 January 1965 it became the 37th Guards Tank Division, staying within 7th Tank Army for the duration.  In 1992 it became part of the Belarus Ground Forces.  The tank division was converted to the 37th Separate Guards Mechanized Brigade, which was disbanded in fall 2011.  The division's lineage currently exists as the 37th Weapons and Equipment Storage Base of the North Western Operational Command at Polotsk.

2S25 Sprut-SD: The 2S25 Sprut-SD (Russian: 2С25 «Спрут-СД»; 2S25 "Kraken-SD") is a self-propelled tank destroyer or light tank developed and manufactured by the Russian defence company, Volgograd tractor factory joint stock company, to meet the requirements of the VDV.  In mid-2001, the Volgograd tractor plant revealed that the development of the 2S25 lasted several years.

Viktor Zholudev: Viktor Grigoryevich Zholudev (Russian: Виктор Григорьевич Жолудев; 22 March 1905 – 21 July 1944) was a Red Army major general and posthumous Hero of the Soviet Union.  Zholudev fought in the 1929 Sino-Soviet conflict, the Battle of Lake Khasan in 1938 and the 1939 Battles of Khalkhin Gol, as well as World War II.  Zholudev commanded the 37th Guards Rifle Division during its defense of the Stalingrad tractor factory during the Battle of Stalingrad.

Kumsong Tractor Factory: The Kŭmsŏng Tractor Factory, located in Kiyang-dong, Kangsŏ-guyŏk, Namp'o, is North Korea's largest manufacturer of tractors, bulldozers, and other agricultural equipment.  Employing around 10,000 workers, the factory has a floor area of 142,000 m2 on a total area of 400,000 m2 .  Although it has a production capacity of 10,000 tractors per year, at present the average annual output is around 200 tractors.  The factory's current products include the "Ch'ŏllima 28" 28 hp , "Ch'ŏllima 32" 32 hp , "Ch'ŏllima 40" 40 hp , "P'ungnyŏn 75" 75 hp , "Sonyŏn" 45 hp and "Ch'ŏllima 2000" tractors, and the "P'ungnyŏn" bulldozer.  This factory also produces TEL mobile missile platforms.

Battle of Stalingrad: The Battle of Stalingrad (23 August 1942 – 2 February 1943) was a major battle of World War II in which Nazi Germany and its allies fought the Soviet Union for control of the city of Stalingrad (now Volgograd) in Southern Russia.

Oleg Kokushkin: Kokushkin was born on 8 May 1910 in Plyos.  His father was an accountant for a textile factory.  In 1912, his family moved to the village of Zakharovo.  From 1917, he lived in Buy, where his father worked at the station.  At Buy Kokushkin graduated from seven classes.  1929, he became a foreman working on the construction of the Stalingrad tractor factory.  He joined the Communist Party in 1931 and the Red Army the same year.

Volgograd Tractor Plant: The Volgograd Tractor Plant (Russian: Волгоградский тракторный завод , "Volgogradski traktorni zavod", or ВгТЗ , "VgTZ"), formerly the "Dzerzhinskiy" Tractor Factory or the Stalingrad Tractor Plant, is a heavy equipment factory located in Volgograd, Russia.  It was a site of fierce fighting during World War II's Battle of Stalingrad.

STZ-5: The STZ-5 artillery tractor was a product of the Stalingrad Tractor Factory (STZ) (Russian: Сталинградский тракторный завод) from 1937 to 1942 in the Soviet Union.  The tractor was designed to tow division to corps level guns and howitzers of 8 tonnes and less.  The STZ-5 was one of the few artillery tractors specifically designed by the Soviet government for its role.  With over 9900 built, it was the most-produced Soviet ‘military’ tractor during the war.

Supporting paragraphs: Viktor Zholudev Battle of Stalingrad
Answer: Volgograd