Hello, is it possible to get timestamp as a var value?

I wat to add timestams as a signal, for using it with adviseLong / Short function I´m trying this:

For example, using Deeplearn.c you get these signals:

Quote
change(1),change(2),change(3),change(4),
range(1),range(2),range(3),range(4)


I wat to add timestamp, but with its usual format, I mean, 20190228 11:58:34

I´ve tried this:
Code
   string datetime_str = strdate("+%Y-%m-%d %H:%M:%S", wdate(0));
    var datetime_var = date(datetime_str);


but does not work. Any clue?

Thank you!