[web2py] use crud to display some fields of a table

[dlin]

I've a table with fields
Field('F1', label='name')
Field('F2', label='data')
....
Field('F20', label='xxx')

I wish use crud to display 5 random  rows of the table, and only
display F1, F2.

So, here is my  code:

ids = [x.values()[0] for x in db().select(db.phmap.id).as_list()]
idr = random.sample(ids, 5)
words  = db(db.phmap.id.belongs(idr)).select(db.phmap.ALL)

I want to display the words with only F1 and F2 fields.
How could I display them by crud.select()?
I want to be smarter to use the already defined labels in db.py,  but
I don't know how to do it.