def index():
    """Produces a list of the feedback obtained for a given venue,
    or for all venues."""
    venue_id = request.args(0)
    if venue_id == 'all':
        q = (db.submission.user == get_user_email())
    else:
        q = ((db.submission.user == get_user_email()) 
            & (db.submission.venue_id == venue_id))
    db.submission.id.represent = lambda x, r: A(T('View'), _class='btn', _href=URL('submission', 'view_own_submission', args=['v', r.id]))
    db.submission.id.label = T('Submission')
    db.submission.id.readable = True
    db.submission.venue_id.readable = True
    grid = SQLFORM.grid(q,
        fields=[db.submission.id, db.submission.venue_id,
                db.submission.date_created, db.submission.date_updated, ],
        csv=False, details=False, create=False, editable=False, deletable=False,
        args=request.args[:1],
        maxtextlength=24,        
        )
    return dict(grid=grid)