📝 Add first tutorial src files

docs/tutorial/src/tutorial47-03.py

@@ -0,0 +1,11 @@
+from fastapi import Body, FastAPI, Path, Query, File
+from pydantic import BaseModel
+from pydantic.types import EmailStr
+from typing import Set, List
+
+app = FastAPI()
+
+
+@app.post("/files/")
+async def create_file(*, file: bytes = File(...)):
+    return {"file_size": len(file)}