fix function line 13

app.py

@@ -10,7 +10,7 @@ def create_postcard(name, tagline, description, events, location, hours, contact
         import base64
         from io import BytesIO
         buffer = BytesIO()
-        logo.save(buffer, format="PNG")
+        logo_file_info.save(buffer, format="PNG")
         logo_base64 = base64.b64encode(buffer.getvalue()).decode('utf-8')
         dwg.add(dwg.image(href=f"data:image/png;base64,{logo_base64}", insert=("10mm", "10mm"), size=("50mm", "50mm")))