diff --git a/projects/PyZpc/pyzfx.cpp b/projects/PyZpc/pyzfx.cpp
index fd98b29f1..19ed144ef 100644
--- a/projects/PyZpc/pyzfx.cpp
+++ b/projects/PyZpc/pyzfx.cpp
@@ -189,8 +189,8 @@ struct PyZfx : INode {
         if (PyDict_SetItemString(zenoModDict, "_args", argsDict) < 0)
             throw makeError("failed to set zpy._args");
  
-        if (has_input("code")) { // path.empty()
-            auto code = get_input2<std::string>("code");
+        auto code = get_input2<std::string>("code");
+        if (!code.empty()) { // path.empty()
             auto tmpFile = zs::abs_exe_directory() + "/__pyzfx__zstmp.py";
             if (std::FILE* f = std::fopen(tmpFile.c_str(), "w")) {
                 std::fwrite(code.data(), sizeof(char), code.size(), f);