diff --git a/depyf/explain/patched_lazy_format_graph_code.py b/depyf/explain/patched_lazy_format_graph_code.py
index 8cfa35da..c258154c 100644
--- a/depyf/explain/patched_lazy_format_graph_code.py
+++ b/depyf/explain/patched_lazy_format_graph_code.py
@@ -2,8 +2,8 @@ def patched_lazy_format_graph_code(name, gm, maybe_id=None, **kwargs):
     from depyf.explain.utils import get_current_compiled_fn_name, write_code_to_file_template
     from depyf.utils import get_code_owner
     func_name = get_current_compiled_fn_name()
-    file_name = name if name != func_name else "Captured Graph"
-    file_name = func_name + " " + file_name
+    file_name = str(name).replace(" ", "_") if name != func_name else "Captured_Graph"
+    file_name = func_name + "_" + file_name
     import inspect
     import os
 
@@ -35,7 +35,7 @@ def patched_lazy_format_graph_code(name, gm, maybe_id=None, **kwargs):
         src = simple_code + commented_src
     if filepath is not None:
         new_filepath = write_code_to_file_template(
-            src, os.path.dirname(filepath) + "/" + file_name + " " + "%s" + ".py")
+            src, os.path.dirname(filepath) + "/" + file_name + "_" + "%s" + ".py")
         scope = fn.__globals__
         exec(compile(src, filename=new_filepath, mode="exec"), scope)
         fn.__code__ = scope[fn.__name__].__code__
diff --git a/depyf/explain/patched_load_by_key_path.py b/depyf/explain/patched_load_by_key_path.py
index adab9afc..73f54471 100644
--- a/depyf/explain/patched_load_by_key_path.py
+++ b/depyf/explain/patched_load_by_key_path.py
@@ -16,6 +16,6 @@ def patched_load_by_key_path(
 
     func_name = get_current_compiled_fn_name()
     new_filepath = write_code_to_file_template(src, os.path.join(
-        dump_src_dir, func_name + " kernel " + "%s" + ".py"))
+        dump_src_dir, func_name + "_kernel_" + "%s" + ".py"))
     path = new_filepath
     return unpatched_load_by_key_path(key, path, linemap, attrs)