Add application file

app.py

@@ -2,9 +2,6 @@ from fastapi import FastAPI
 
 app = FastAPI()
 
-@app.get("/hello")
-def hello():
-    """
-    This Test Hello
-    """
-    return {"Hello":"You succefully deploy youtube"}
+@app.get("/")
+def greet_json():
+    return {"Hello": "World!"}