feat: First comit

app.py

@@ -388,14 +388,20 @@ async def predict_file(file: UploadFile = File(...), steps: int = 10) -> Predict
         try:
             df = pd.read_csv(io.BytesIO(content))
         except Exception:
-            # If CSV fails, try Excel
-            try:
-                df = pd.read_excel(io.BytesIO(content))
-            except Exception as exc2:
+            # If CSV fails, try Excel with multiple engines
+            excel_read_error = None
+            for engine in ("openpyxl", "xlrd"):
+                try:
+                    df = pd.read_excel(io.BytesIO(content), engine=engine)
+                    break
+                except Exception as exc_excel:
+                    excel_read_error = exc_excel
+                    df = None
+            if df is None:
                 raise HTTPException(
                     status_code=400,
-                    detail=f"could not read file as CSV or Excel: {exc2}"
-                ) from exc2
+                    detail=f"could not read file as CSV or Excel: {excel_read_error}"
+                ) from excel_read_error
     except Exception as exc:
         raise HTTPException(status_code=400, detail=f"could not read file: {exc}") from exc