diff --git a/_pydemo/pi/pi.go b/_pydemo/pi/pi.go
new file mode 100644
index 00000000..934fe31a
--- /dev/null
+++ b/_pydemo/pi/pi.go
@@ -0,0 +1,10 @@
+package main
+
+import (
+	"github.com/goplus/llgo/c"
+	"github.com/goplus/llgo/py/math"
+)
+
+func main() {
+	c.Printf(c.Str("pi = %f\n"), math.Pi)
+}
diff --git a/_xtool/llpyg/llpyg.go b/_xtool/llpyg/llpyg.go
index 9dac48a5..eea35c6b 100644
--- a/_xtool/llpyg/llpyg.go
+++ b/_xtool/llpyg/llpyg.go
@@ -44,8 +44,11 @@ func main() {
 		key := item.TupleItem(0)
 		val := item.TupleItem(1)
 		if val.Callable() != 0 {
+			doc := val.GetAttrString(c.Str("__doc__"))
 			sig := inspect.Signature(val)
+			c.Fprintf(c.Stderr, c.Str("-----------------------------------\n"))
 			c.Fprintf(c.Stderr, c.Str("%s: %s\n"), key.CStr(), sig.Str().CStr())
+			c.Fprintf(c.Stderr, c.Str("%s\n"), doc.CStr())
 		}
 	}
 }
diff --git a/py/exceptions.go b/py/exceptions.go
new file mode 100644
index 00000000..cd9da49d
--- /dev/null
+++ b/py/exceptions.go
@@ -0,0 +1,32 @@
+/*
+ * Copyright (c) 2024 The GoPlus Authors (goplus.org). All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package py
+
+import (
+	_ "unsafe"
+)
+
+// https://docs.python.org/3/c-api/exceptions.html
+
+// Clear the error indicator. If the error indicator is not set, there is
+// no effect.
+//
+//go:linkname ErrClear C.PyErr_Clear
+func ErrClear()
+
+//go:linkname ErrPrint C.PyErr_Print
+func ErrPrint()
diff --git a/py/math/math.go b/py/math/math.go
index 7bfd8ebe..d65531ff 100644
--- a/py/math/math.go
+++ b/py/math/math.go
@@ -28,3 +28,6 @@ const (
 
 //go:linkname Sqrt py.sqrt
 func Sqrt(x *py.Object) *py.Object
+
+//go:linkname Pi py.pi
+var Pi *py.Object
diff --git a/py/module.go b/py/module.go
index 6f33cfaf..163d0555 100644
--- a/py/module.go
+++ b/py/module.go
@@ -22,8 +22,17 @@ import (
 	"github.com/goplus/llgo/c"
 )
 
+// https://docs.python.org/3/c-api/import.html
 // https://docs.python.org/3/c-api/module.html
 
+// Return the module object corresponding to a module name. The name argument
+// may be of the form package.module. First check the modules dictionary if
+// there’s one there, and if not, create a new one and insert it in the modules
+// dictionary. Return nil with an exception set on failure.
+//
+//go:linkname AddModule C.PyImport_AddModule
+func AddModule(name *c.Char) *Object
+
 // This is a wrapper around py.Import which takes a const char* as an argument
 // instead of an Object.
 //