def sample_labels(model, wkrs, imgs):
    """
    Generate a full labeling by workers given worker and image parameters.
    
    Input:
    - `model`: model instance to use for sampling parameters and labels.
    - `wkrs`: list of worker parameters.
    - `imgs`: list of image parameters.
    
    Output:
    1. list [img id, wkr id, label] as provided by `model.sample_label`.
    """
    labels = [[ii, wi, model.sample_label(wkrs[wi], imgs[ii])] \
              for ii in range(len(imgs)) for wi in range(len(wkrs))]
    return labels