now can show Lost books from menu

main.py

@@ -1031,6 +1031,12 @@ def FindMissingBooks():
                 books.append( { 'id': t.id, 'title': t.title, 'num_books': t.num_books, 'missing': str(missing)[1:-1] } )
     return books
 
+@app.route("/lost", methods=["GET"])
+@login_required
+def lost():
+    books = Book.query.join(Owned).filter(Owned.name=='Lost').all()
+    return render_template("books.html", books=books, page_title="Lost Books", show_cols='', hide_cols='Publisher' )
+
 @app.route("/missing_books", methods=["GET"])
 @login_required
 def missing_books():