图像赢得'；t在dash-python中加载

我在我的应用程序中创建了一个if语句来加载图像。如果情感为回调的==值，则在应用程序中加载图像

# load image for sentiment

if overall_sentiment == "fear":
  image_filename = "fear.png" 
  image = base64.b64encode(open(image_filename, 'rb').read()).decode('ascii')
if overall_sentiment == "sadness":
  image_filename = "sadness.png" 
  image = base64.b64encode(open(image_filename, 'rb').read()).decode('ascii')
if overall_sentiment == "anger":
  image_filename = "anger.png" 
  image = base64.b64encode(open(image_filename, 'rb').read()).decode('ascii')
if overall_sentiment == "disgust":
  image_filename = "disgust.png" 
  image = base64.b64encode(open(image_filename, 'rb').read()).decode('ascii')
if overall_sentiment == "enjoyment":
  image_filename = "enjoyment" 
  image = base64.b64encode(open(image_filename, 'rb').read()).decode('ascii')

我在我的应用程序中加载图像，如下所示：

    html.Img(
         html.H4("Overall sentiment"),
         id ="overall_sentiment",
         src='data:image/png;base64,{}'.format(image)
        )])

由于某些原因，图像将不会显示