Update post_blog.py

post_blog.py

@@ -26,7 +26,7 @@ def generate_image(title, summary, category):
     with open("image.png", "wb") as file:
         file.write(data)
     encoded_image = base64.b64encode(data)
-    image =  f"data:image/png;base64,{encoded_image.decode("utf-8")}"
+    image =  f"data:image/png;base64,{encoded_image.decode('utf-8')}"
     return image
 
 def generate_post_html(title, summary, mindmap, category, citation):