+
+# Those will be generated only for books with own HTML.
+EBOOK_FORMATS_WITHOUT_CHILDREN = ['txt', 'fb2']
+# Those will be generated for all books.
+EBOOK_FORMATS_WITH_CHILDREN = ['pdf', 'epub', 'mobi']
+# Those will be generated when inherited cover changes.
+EBOOK_FORMATS_WITH_COVERS = ['mobi']
+
+EBOOK_FORMATS = EBOOK_FORMATS_WITHOUT_CHILDREN + EBOOK_FORMATS_WITH_CHILDREN