was she into fashion before becoming a journalist?
Yes, she took up her first job at the influential Biba boutique and also took fashion classes at a school.
Anna Wintour
He arranged for his daughter's first job, at the influential Biba boutique, when she was 15. The next year, she left North London Collegiate and began a training program at Harrods. At her parents' behest, she also took fashion classes at a nearby school. 
who is miranda from devil wears prada based on Anna Wintour who is she? She is a British-American journalist and editor.
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Anna Wintour [SEP] From fashion to journalism
"I think my father really decided for me that I should work in fashion," she recalled in "The September Issue". He arranged for his daughter's first job, at the influential Biba boutique, when she was 15. The next year, she left North London Collegiate and began a training program at Harrods. At her parents' behest, she also took fashion classes at a nearby school. Soon she gave them up, saying, "You either know fashion or you don't." Another older boyfriend, Richard Neville, gave her her first experience of magazine production at his popular and controversial "Oz". In 1970, when "Harper's Bazaar UK" merged with "Queen" to become "Harper's & Queen", Wintour was hired as one of its first editorial assistants, beginning her career in fashion journalism.