如何处理XML转换成图片过程中的错误？

import xml.etree.ElementTree as ET
from PIL import Image, ImageDraw, ImageFont

def xml_to_image(xml_file, output_file):
    try:
        tree = ET.parse(xml_file)
        root = tree.getroot()

        width = int(root.get('width'))
        height = int(root.get('height'))
        img = Image.new('RGB', (width, height), 'white')
        draw = ImageDraw.Draw(img)

        for bar in root.findall('bar'):
            x = int(bar.get('x'))
            y = int(bar.get('y'))
            w = int(bar.get('width'))
            h = int(bar.get('height'))
            color = bar.get('color')  #  注意这里，颜色处理需要小心

            try:
                draw.rectangle([(x, y), (x + w, y + h)], fill=color)
            except ValueError:
                print(f"Invalid color value: {color} for bar at {x}, {y}")
                #  这里可以做更优雅的处理，比如用默认颜色

        img.save(output_file)

    except ET.ParseError as e:
        print(f"XML parsing error: {e}")
    except FileNotFoundError:
        print(f"XML file not found: {xml_file}")
    except Exception as e: #  捕获所有其他异常，方便调试
        print(f"An unexpected error occurred: {e}")

#  使用方法
xml_to_image("my_chart.xml", "chart.png")