Question: What was the estimated 2009 population of the city in which Thorngate, South Australia is located?

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List of mayors of Shiraz: This is a list of mayors of Shiraz.  It is the sixth most populous city in Iran and is the capital of Fars Province.  The city's 2009 population was 1,455,073.  Shiraz is located in the southwest of Iran on the Roodkhaneye Khoshk (Dry river).

City of Onkaparinga: The City of Onkaparinga is a local government area (LGA) located on the southern fringe of Adelaide, South Australia.  It is named after the Onkaparinga River, whose name comes from "Ngangkiparinga", a Kaurna word meaning women's river.  It is the largest LGA in South Australia, with an estimated population of 164,800 people in both urban and rural communities and is also geographically expansive, encompassing an area of 518.3 km².  The council is headquartered in the Noarlunga Centre with area offices situated in Aberfoyle Park, Woodcroft and Willunga.

Thorngate, South Australia: Thorngate is an inner northern suburb of Adelaide, South Australia.  It is located in the City of Prospect.

Adelaide: Adelaide ( ) is the capital city of the state of South Australia, and the fifth-most populous city of Australia.  In June 2016, Adelaide had an estimated resident population of 1,326,354.  South Australia, with a total of 1.7 million inhabitants, has the most centralised population of any state in Australia, with more than 75 percent of its people living in greater Adelaide, while the other population centres in the state are relatively small.

City of Prospect: The City of Prospect is an inner urban local government area (LGA) in Adelaide, South Australia.  Established in 1872, it is one of the oldest LGAs in South Australia.  s of 2009 the population is estimated at 21,000.

Fitzroy, South Australia: Fitzroy is an inner northern suburb of Adelaide 4 km from the Adelaide city centre, in the state of South Australia, Australia within the City of Prospect.  It is adjacent to North Adelaide, Prospect, Ovingham and Thorngate.  The post code for Fitzroy is 5082.  It is bounded to the west by Cotton Street, to the south by Fitzroy Terrace, in the east by Prospect Road and the north by Avenue Road.  Fitzroy is essentially a residential suburb, overlooking the North Adelaide Parklands.

Brighton Town Hall, Adelaide: Brighton Town Hall, Hove, is located on Brighton Road, Hove, in the city of Adelaide in South Australia.  The Brighton Town Hall was built in 1869 and was just the fourth Town Hall built in the colony of South Australia.  The architect and builder was George William Highet who arrived in the colony in 1836.  G. W. Highet served as a town clerk and Councillor and died in Brighton aged 80 years.  The hall was constructed of stone from Ayliffe’s quarry in the Adelaide Hills laid on concrete foundations.  The pioneers built it not just as a place for the business of Government but as a place "to serve the wants of the citizens" for many different activities.  On 10 May 1869 a foundation stone was laid by the Hon John Hodgkiss a member of the Legislative Council of South Australia in a ceremony attended by many of South Australia's most important pioneers.  Under this stone was placed a time capsule containing copies of the newspapers of the day.

City of Victor Harbor: The City of Victor Harbor is a local government area of South Australia.  It covers an area of 386.5 km2 along the coast about 80 km south of the centre of Adelaide, the capital of South Australia.  The council is responsible for the town of Victor Harbor, which contains over 85% of its population, and the surrounding rural area to the north and west.  The City of Victor Harbor has an estimated population of 13,608.

Solingen: Solingen (] ) is a city in North Rhine-Westphalia, Germany.  It is located on the northern edge of the region called Bergisches Land, south of the Ruhr area, and with a 2009 population of 161,366 is after Wuppertal the second largest city in the Bergisches Land.  It is a member of the regional authority of the Rhineland.

New South Wales: New South Wales (abbreviated as NSW) is a state on the east coast of :Australia.  It borders Queensland to the north, Victoria to the south, and South Australia to the west.  Its coast borders the Tasman Sea to the east.  The Australian Capital Territory is an enclave within the state.  New South Wales' state capital is Sydney, which is also Australia's most populous city.  In March 2014 , the estimated population of New South Wales was 7.5 million, making it Australia's most populous state.  Just under two-thirds of the state's population, 4.67 million, live in the Greater Sydney area.  Inhabitants of New South Wales are referred to as "New South Welshmen".

Supporting paragraphs: Thorngate, South Australia City of Prospect
Answer: 21,000