JHUMPA LAHIRI WASN’T SURE SHE COULD BE A WRITER. Although as a child she had harbored dreams of doing just that, they had gradually been eaten away by self-doubt — she could scarcely believe the books she loved had been written by real people.  “At twenty-one,” she recalled in a 2011 New Yorker essay, “the writer in me was like a fly in the room — alive but insignificant, aimless, something that unsettled me whenever I grew aware of it, and which, for the most part, left me alone.”