Make a dictionary to print.

def _options_to_dict(df):
    """Make a dictionary to print."""
    kolums = ["k1", "k2", "value"]
    d = df[kolums].values.tolist()
    dc = {}
    for x in d:
        dc.setdefault(x[0], {})
        dc[x[0]][x[1]] = x[2]
    return dc