Update app.py

app.py

@@ -15,7 +15,7 @@ mermaid_code = """graph TD;
 
 
 #def call_chart(mermaidCode):
-def mm(graph=mermaid_code):
+def mm(graph):
     code_out=""
     for ea in mermaid_code.split("\n"):
         code=ea.strip().strip("\n")