With this code:
{% for o in [1,2,3] %} {% cycle \'row1\' \'row2\' %} {% endf
You can do it via cunning use of the make_list filter, but it's probably a bad idea:
{% for o in "123"|make_list %} {% cycle 'row1' 'row2' %} {% endfor %}
p.s. You don't seem to be using o anywhere, so I'm not sure what you're trying to do.
o