add missing instructor for bool_
diff --git a/include/pybind11/pytypes.h b/include/pybind11/pytypes.h
index 7d7cd9f..48e3d1f 100644
--- a/include/pybind11/pytypes.h
+++ b/include/pybind11/pytypes.h
@@ -264,6 +264,7 @@
 class bool_ : public object {
 public:
     PYBIND11_OBJECT_DEFAULT(bool_, object, PyBool_Check)
+    bool_(bool value) : object(value ? Py_True : Py_False, true) { }
     operator bool() const { return m_ptr && PyLong_AsLong(m_ptr) != 0; }
 };