def get_randomdata(df, n=None, frac=None):
    """ Returns n or a fraction of randomly chosen rows.

    Parameters:
    ----------
    n : int, optional, default=None
        Number of items from axis to return. Cannot be used with `frac`.

    frac : float, optional, default=None
        Fraction of axis items to return. Cannot be used with `n`.

    Returns
    ----------
    df_sample : dataframe

    """
    if n is not None or frac is not None:
        # Randomly sample num_samples elements from dataframe
        df_sample = df.sample(n=n, frac=frac).iloc[:, 1:]
    else:
        df_sample = df.sample(n=100).iloc[:, 1:]
    return df_sample