aとbを統合してcのような配列を作成する美しいpythonのコードを書け
a = [{"word":"a","tfidf":0.5},
{"word":"b","tfidf":0.1},
{"word":"c","tfidf":0.2}]
b = [{"word":"d","tfidf":0.3},
{"word":"a","tfidf":0.2},
{"word":"c","tfidf":0.4}]
c = [{"word":"a","tfidf":0.7},
{"word":"b","tfidf":0.1},
{"word":"c","tfidf":0.6},
{"word":"d","tfidf":0.3}]