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Britney Spears preforms live during the opening night for her residency show ‘Britney: Piece Of Me’ at The AXIS inside the Planet Hollywood Resort and Casino on December 27, 2013 in Las Vegas, Nevada (SplashNews)

Britney Spears preforms live during the opening night for her residency show ‘Britney: Piece Of Me’ at The AXIS inside the Planet Hollywood Resort and Casino on December 27, 2013 in Las Vegas, Nevada (SplashNews)

Britney Spears preforms live during the opening night for her residency show ‘Britney: Piece Of Me’ at The AXIS inside the Planet Hollywood Resort and Casino on December 27, 2013 in Las Vegas, Nevada (SplashNews)

Britney Spears preforms live during the opening night for her residency show ‘Britney: Piece Of Me’ at The AXIS inside the Planet Hollywood Resort and Casino on December 27, 2013 in Las Vegas, Nevada (SplashNews)

Britney Spears preforms live during the opening night for her residency show ‘Britney: Piece Of Me’ at The AXIS inside the Planet Hollywood Resort and Casino on December 27, 2013 in Las Vegas, Nevada (SplashNews)

Britney Spears preforms live during the opening night for her residency show ‘Britney: Piece Of Me’ at The AXIS inside the Planet Hollywood Resort and Casino on December 27, 2013 in Las Vegas, Nevada (SplashNews)

Britney Spears preforms live during the opening night for her residency show ‘Britney: Piece Of Me’ at The AXIS inside the Planet Hollywood Resort and Casino on December 27, 2013 in Las Vegas, Nevada (SplashNews)

Britney Spears preforms live during the opening night for her residency show ‘Britney: Piece Of Me’ at The AXIS inside the Planet Hollywood Resort and Casino on December 27, 2013 in Las Vegas, Nevada (SplashNews)

Britney Spears preforms live during the opening night for her residency show ‘Britney: Piece Of Me’ at The AXIS inside the Planet Hollywood Resort and Casino on December 27, 2013 in Las Vegas, Nevada (SplashNews)

Britney Spears preforms live during the opening night for her residency show ‘Britney: Piece Of Me’ at The AXIS inside the Planet Hollywood Resort and Casino on December 27, 2013 in Las Vegas, Nevada (SplashNews)

Britney Spears preforms live during the opening night for her residency show ‘Britney: Piece Of Me’ at The AXIS inside the Planet Hollywood Resort and Casino on December 27, 2013 in Las Vegas, Nevada (SplashNews)

Britney Spears preforms live during the opening night for her residency show ‘Britney: Piece Of Me’ at The AXIS inside the Planet Hollywood Resort and Casino on December 27, 2013 in Las Vegas, Nevada (SplashNews)

Britney Spears preforms live during the opening night for her residency show ‘Britney: Piece Of Me’ at The AXIS inside the Planet Hollywood Resort and Casino on December 27, 2013 in Las Vegas, Nevada (SplashNews)

Doe B (Courtesy of Instagram)