def color_formatter(col_name_list):
    """This function takes in a list of dataframe column names and then
    converts them to standardized colors so that the final graphs show 
    each fuel type using the same color.
    """
    color_dict = {}
    
    for col_name in col_name_list:
        if 'natural' in col_name.lower():
            color_dict[col_name] = '#1f78b4'
        elif 'fuel' in col_name.lower():
            color_dict[col_name] = '#e31a1c'
        elif 'water' in col_name.lower():
            color_dict[col_name] = '#b3df8a'
        elif 'sewer' in col_name.lower():
            color_dict[col_name] = '#fdbf6f'
        elif 'district' in col_name.lower():
            color_dict[col_name] = '#fb9a99'
        elif 'kw_' in col_name.lower() or 'demand' in col_name.lower():
            color_dict[col_name] = '#33a02c'
        elif 'electricity' in col_name.lower() or 'kwh' in col_name.lower() or 'Electricity' in col_name:
            color_dict[col_name] = '#a6cee3'
        elif 'refuse' in col_name.lower():
            color_dict[col_name] = '#ff7f00'
        elif 'propane' in col_name.lower():
            color_dict[col_name] = '#cab2d6'
        elif 'wood' in col_name.lower():
            color_dict[col_name] = '#6a3d9a'
        else:
            color_dict[col_name] = '#000000'
            
    return color_dict