diff --git a/pyext/ctbin.i b/pyext/ctbin.i
index d5c4f87..a8aa1e3 100644
--- a/pyext/ctbin.i
+++ b/pyext/ctbin.i
@@ -18,6 +18,7 @@
 %{
 /* Put headers and other declarations here that are needed for compilation */
 #include "ctbin.hpp"
+#include "GTools.hpp"
 %}
 %include gammalib.i
 
@@ -25,7 +26,7 @@
 /***********************************************************************//**
  * @class ctbin
  *
- * @brief CTA data binning tool Python interface defintion
+ * @brief CTA data binning tool Python interface
  ***************************************************************************/
 class ctbin : public GApplication  {
 public:
@@ -48,7 +49,7 @@ public:
 
 
 /***********************************************************************//**
- * @brief CTA data binning tool SWIG extension
+ * @brief CTA data binning tool Python extension
  ***************************************************************************/
 %extend ctbin {
     ctbin copy() {
diff --git a/pyext/ctlike.i b/pyext/ctlike.i
index 5bc4c64..d658ddc 100644
--- a/pyext/ctlike.i
+++ b/pyext/ctlike.i
@@ -18,6 +18,7 @@
 %{
 /* Put headers and other declarations here that are needed for compilation */
 #include "ctlike.hpp"
+#include "GTools.hpp"
 %}
 %include gammalib.i
 
@@ -25,7 +26,7 @@
 /***********************************************************************//**
  * @class ctlike
  *
- * @brief CTA maximum likelihood tool Python interface defintion
+ * @brief CTA maximum likelihood tool Python interface
  ***************************************************************************/
 class ctlike : public GApplication  {
 public:
@@ -50,7 +51,7 @@ public:
 
 
 /***********************************************************************//**
- * @brief CTA maximum likelihood tool SWIG extension
+ * @brief CTA maximum likelihood tool Python extension
  ***************************************************************************/
 %extend ctlike {
     ctlike copy() {
diff --git a/pyext/ctobssim.i b/pyext/ctobssim.i
index d025643..5e237d7 100644
--- a/pyext/ctobssim.i
+++ b/pyext/ctobssim.i
@@ -12,12 +12,13 @@
  ***************************************************************************/
 /**
  * @file ctobssim.i
- * @brief CTA observation simulation tool python interface definition
+ * @brief CTA observation simulation tool Python interface definition
  * @author J. Knodlseder
  */
 %{
 /* Put headers and other declarations here that are needed for compilation */
 #include "ctobssim.hpp"
+#include "GTools.hpp"
 %}
 %include gammalib.i
 
@@ -25,7 +26,7 @@
 /***********************************************************************//**
  * @class ctobssim
  *
- * @brief CTA data selection tool python interface defintion.
+ * @brief CTA data selection tool Python interface
  ***************************************************************************/
 class ctobssim : public GApplication  {
 public:
@@ -51,7 +52,7 @@ public:
 
 
 /***********************************************************************//**
- * @brief CTA observation simulation tool extension
+ * @brief CTA observation simulation tool Python extension
  ***************************************************************************/
 %extend ctobssim {
     ctobssim copy() {
diff --git a/pyext/ctselect.i b/pyext/ctselect.i
index 5f08576..461f8ff 100644
--- a/pyext/ctselect.i
+++ b/pyext/ctselect.i
@@ -1,7 +1,7 @@
 /***************************************************************************
  *                    ctselect - CTA data selection tool                   *
  * ----------------------------------------------------------------------- *
- *  copyright (C) 2010 by Jurgen Knodlseder                                *
+ *  copyright (C) 2010-2011 by Jurgen Knodlseder                           *
  * ----------------------------------------------------------------------- *
  *                                                                         *
  *   This program is free software; you can redistribute it and/or modify  *
@@ -12,12 +12,13 @@
  ***************************************************************************/
 /**
  * @file ctselect.i
- * @brief CTA data selection tool SWIG definition
+ * @brief CTA data selection tool Python interface definition
  * @author J. Knodlseder
  */
 %{
 /* Put headers and other declarations here that are needed for compilation */
 #include "ctselect.hpp"
+#include "GTools.hpp"
 %}
 %include gammalib.i
 
@@ -25,25 +26,30 @@
 /***********************************************************************//**
  * @class ctselect
  *
- * @brief CTA data selection tool SWIG interface defintion.
+ * @brief CTA data selection tool Python interface
  ***************************************************************************/
 class ctselect : public GApplication  {
 public:
     // Constructors and destructors
     ctselect(void);
+    explicit ctselect(GObservations obs);
     ctselect(int argc, char *argv[]);
-    ~ctselect(void);
+    ctselect(const ctselect& app);
+    virtual ~ctselect(void);
 
     // Methods
-    void run(void);
-    void get_parameters(void);
-    void select(void);
-    void append_gti(void);
+    void           clear(void);
+    void           execute(void);
+    void           run(void);
+    void           save(void);
+    GObservations& obs(void) { return m_obs; }
+    void           get_parameters(void);
+    void           select_events(GCTAObservation* obs, const std::string& filename);
 };
 
 
 /***********************************************************************//**
- * @brief CTA data selection tool SWIG extension
+ * @brief CTA data selection tool Python extension
  ***************************************************************************/
 %extend ctselect {
     ctselect copy() {