Question: For how many weeks has the athlete who defended her title in the 2007 Acura Classic-Singles been ranked world No 1 by the WTA?

full_context: Document 1: Maria Sharapova: Maria Yuryevna Sharapova (Russian: Мари́я Ю́рьевна Шара́пова ; ] ; born April 19, 1987) is a Russian professional tennis player. A United States resident since 1994, Sharapova has competed on the WTA tour since 2001. She has been ranked world No. 1 in singles by the WTA on five separate occasions, for a total of 21 weeks. She is one of ten women, and the only Russian, to hold the career Grand Slam. She is also an Olympic medalist, having earned silver for Russia in women's singles at the 2012 Summer Olympics in London.
Document 2: 2008 Bausch &amp; Lomb Championships – Singles: The 2008 Bausch & Lomb Championships – Singles was the singles event of the 2008 Bausch & Lomb Championships, a WTA Tier II tennis tournament held in April. Tatiana Golovin was the defending champion, but withdrew from this year's event with injury. Maria Sharapova defeated Dominika Cibulková in the final to become the 2008 champion. This was Sharapova's 19th career singles title but the first she had won on clay courts.
Document 3: 2007 Acura Classic: The 2007 Acura Classic was a tennis tournament played on outdoor hard courts in San Diego in the United States. It was part of Tier I of the 2007 WTA Tour. The tournament was held from July 30 through August 5, 2007.
Document 4: Vera Zvonareva: Vera Igorevna Zvonareva (Russian: Ве́ра И́горевна Звонарёва ; ] ; born 7 September 1984) is a Russian professional tennis player. She was introduced to tennis at the age of six and turned professional in 2000. Her career high is world No. 2 by the WTA. Zvonareva has won twelve WTA Tour singles titles and reached the finals of the 2008 WTA Tour Championships, 2010 Wimbledon Championships, and 2010 US Open. She also was a bronze medalist at the 2008 Beijing Olympics. In doubles, she has won four Grand Slam titles. Two of the titles came in women's doubles, the first one at the 2006 US Open, partnering Nathalie Dechy, and the other at the 2012 Australian Open, partnering Svetlana Kuznetsova. Her other two came in mixed doubles, the first at the 2004 US Open, partnering Bob Bryan, and her second at the 2006 Wimbledon Championships, partnering Andy Ram.
Document 5: 2014 Maria Sharapova tennis season: The 2014 Maria Sharapova tennis season officially began on 30 December 2013 with the start of the 2014 WTA Tour. Sharapova began the season, having only played one match since the previous June due to a shoulder injury, at the Brisbane International. After failing to defend her points during the winter and spring hard court season, Sharapova almost dropped out of the Top 10. She rebounded by dominating the clay court season which saw her win Stuttgart, Madrid and the French Open. Her only loss on clay came to a resurgent Ana Ivanovic. She then won her first hard court title since the 2013 BNP Paribas Open at the China Open. Her season ended on 24 October 2014 following her elimination from the round robin stage at the 2014 WTA Finals in Singapore. She ended the year raned No. 2 behind Serena Williams.
Document 6: 2007 China Open – Women's Doubles: Virginia Ruano Pascual and Paola Suárez were the defending champions, but Suarez retired from the sport on September 1, 2007, and only Ruano Pascual competed that year.
Document 7: 2007 Sony Ericsson International – Singles: Yaroslava Shvedova won the title, beating defending champion Mara Santangelo 6–4, 6–4 in the final.
Document 8: 2007 Acura Classic – Singles: Maria Sharapova successfully defended her title, by defeating Patty Schnyder in the final.
Document 9: Anna Kournikova: Anna Sergeyevna Kournikova (Russian: А́нна Серге́евна Ку́рникова ; ] ; born 7 June 1981) is a Russian former professional tennis player. Her appearance and celebrity status made her one of the best known tennis stars worldwide. At the peak of her fame, fans looking for images of Kournikova made her name one of the most common search strings on Google Search.
Document 10: Anastasia Myskina: Anastasiya Andreyevna Myskina (Russian: Анастасия Андреевна Мыскина ; ] ; born 8 July 1981) is a Russian former tennis player. She won the 2004 French Open singles title, becoming the first Russian female tennis player to win a Grand Slam singles title. Subsequent to this victory, she rose to No. 3 in the WTA rankings, becoming the first Russian female tennis player to reach the top 3 in the history of the rankings. In September 2004, she reached a career-high ranking of No. 2. She has not officially retired, but has been inactive on the WTA Tour since May 2007.
Document 11: Maria Kirilenko: Maria Yuryevna Kirilenko-Stepanova (Russian: Мари́я Ю́рьевна Кириле́нко ; ] ; born 25 January 1987) is a Russian tennis player. Kirilenko won the 2002 U.S. Open Girls' Singles and won her first WTA Tour title in 2005, defeating Anna-Lena Grönefeld in the China Open. She has reached three Grand Slam singles quarterfinals, at the 2010 Australian Open the 2012 Wimbledon Championships and the 2013 French Open. In doubles, she has reached two Grand Slam doubles finals, at the 2011 Australian Open and the 2012 French Open, won the 2012 WTA Tour Championships and was a bronze medalist at the 2012 London Olympics. In June 2013, Kirilenko reached her career high ranking of World No. 10.
Document 12: Elena Dementieva: Elena Viacheslavovna Dementieva (Russian: Еле́на Вячесла́вовна Деме́нтьева , ] ; born 15 October 1981) is a retired Russian tennis player. Dementieva won the singles gold medal at the 2008 Olympics in Beijing, having previously won the silver medal at the 2000 Olympics in Sydney. She won 16 WTA singles titles, reached the finals of the 2004 French Open and 2004 US Open and reached seven other Grand Slam semi finals. Dementieva was also part of the Russian team that won the 2005 Fed Cup, won the 2002 WTA Championship doubles with Janette Husárová and was the runner-up in two US Open doubles finals – in 2002 with Husárová and in 2005 with Flavia Pennetta. Dementieva achieved a career-high ranking of World No. 3, which was accomplished on 6 April 2009. She announced her retirement on 29 October 2010, after her final match at the 2010 WTA Tour Championships. Dementieva ended her career ranked World No. 9 and between 2003 and 2010 she only ended one year, in 2007, outside the top 10.
Document 13: Serena Williams: Serena Jameka Williams (born September 26, 1981) is an American professional tennis player. The Women's Tennis Association (WTA) has ranked her world No. 1 in singles on eight occasions, from 2002 to 2017. She became the world No. 1 for the first time on July 8, 2002. On the sixth occasion, she held the ranking for 186 consecutive weeks, tying the record set by Steffi Graf for the most consecutive weeks as world No. 1 by a female tennis player. In total, she has been world No. 1 for 319 weeks, which ranks her third in the Open Era among female tennis players. Some commentators, players and sports writers regard her as the greatest female tennis player of all time.
Document 14: Maria Sharapova career statistics: This is a list of the main career statistics of professional Russian tennis player, Maria Sharapova. To date, Sharapova has won thirty five WTA singles titles including five Grand Slams, one year-ending championship, six WTA Tier I singles titles, three WTA Premier Mandatory singles titles and five WTA Premier 5 singles titles. She was also the silver medallist in singles at the 2012 London Olympics.
Document 15: 2007 Acura Classic – Doubles: Cara Black and Rennae Stubbs were the defending champions but chose to participate with different partners. Stubbs teamed up with Kveta Peschke and was eliminated in the second round. Black paired up with Liezel Huber and together they won the title after defeating Victoria Azarenka and Anna Chakvetadze 7–5, 6–4 in the final.
ground_truth: 21