def create_label_column(row) -> str:
    """
    Helper function to generate a new column which will be used
    to label the choropleth maps. Function used to label missing data
    (otherwise they will show up on the map as "-1 SEK").

    Parameters
    ----------
    row :

    Returns
    -------
    str
        Column label to show when user hovers mouse over a choropleth map.
    """
    if row["Median Rent (SEK)"] > 0:
        return "Median Cost: " + str(int(row["Median Rent (SEK)"])) + " SEK"
    else:
        return "Missing Data"