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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def book_name(self, number):
        '''Return name of book with given index.'''
        try:
            name = self.cur.execute("SELECT name FROM book WHERE number = ?;", [number]).fetchone()
        except:
            self.error("cannot look up name of book number %s" % number)
        return(str(name[0]))