'Represent a (key, value) as hypertext link
@param k: the key (dvr_activity.id)
@param v: the representation of the key
@param row: the row with this key (unused here)'

def link(self, k, v, row=None):

    url = URL(c='dvr', f='activity', args=[k], extension='')
    return A(v, _href=url)
