def add_lat_long_coordinates(art_no_lat_lon_df, col_name):
    """
    Parameters
    ----------
    art_no_lat_lon_df (dataframe object) contains dataframe with column col_name containing coordinates in a list
    col_name (string) name of column
    
    Returns
    -------
    art_df (dataframe object) dataframe with new columns latitude and longitue
    
    """
    
    art_df = art_no_lat_lon_df.copy()
    
    # After removing empty entries, we can then iterate over them
    clean_list_of_coordinates = art_df[col_name].to_list()

    # not super efficient way of doing things, but they get it done
    latitude = []
    longitude = []
    # Iterate over every pair of coordinates
    for item in clean_list_of_coordinates:
        longitude.append(item[0])
        latitude.append(item[1])
        
    art_df['latitude'] = latitude
    art_df['longitude'] = longitude
    
    return art_df