'her signature sartorial style'? Introduced by her daughter, Chelsea, who called her “my hero,” Mrs. Clinton was met with a lengthy, loud standing ovation. She sprinkled her opening remarks with personal touches, delighting the crowd by thanking “my supporters, my champions — my sisterhood of the traveling pantsuits,” a reference to her signature sartorial style.
question:1,meaning of 'my sisterhood of the traveling pantsuits';2,meaning of 'her signature sartorial style'

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