docs: def create_book(self, name):
          """Create a new book"""
          name = name.strip()
          if not len(name):
              self.error("Cannot have a blank book name")
          # The next could be relaxed, if users want commas in book names, but
          # I prefer to keep it, in case later there could be a syntax for multiple
          # book names, using comma.
          if name.find(",") >= 0:
              self.error("Cannot have a ',' in a book name")
          existing = self.list_books()
          nexisting = len(existing)
          if name in existing:
              self.error("Already have a book named '%s'" % name)
          try:
              self.cur.execute("INSERT INTO book (number, name) VALUES(?, ?);", (nexisting, name))
              self.con.commit()
          except:
              self.fyi("Error adding a book named '%s'" % name)