diff --git a/ChangeLog b/ChangeLog
index f4d9bc6..2199a02 100755
--- a/ChangeLog
+++ b/ChangeLog
@@ -12,6 +12,14 @@
         Add support of rectangular On/Off regions (#3248)
 
 
+2020-12-02
+
+        * Bug fix version 1.7.3 released
+        ================================
+
+        Import matplotlib first in example scripts (#3423)
+
+
 2020-10-15
 
         * Bug fix version 1.7.2 released
diff --git a/doc/source/admin/download.rst b/doc/source/admin/download.rst
index 948ee2b..d3dc9b0 100755
--- a/doc/source/admin/download.rst
+++ b/doc/source/admin/download.rst
@@ -3,7 +3,7 @@
 Download
 ========
 
-The latest ctools release is ``ctools-1.7.2`` (15 October 2020).
+The latest ctools release is ``ctools-1.7.3`` (2 December 2020).
 
 Below a table of ctools releases. Please read the :ref:`sec_release` to
 learn more about new features and corrected bugs in a given release.
@@ -11,7 +11,7 @@ learn more about new features and corrected bugs in a given release.
 .. warning::
    At this stage of the project there is a strict link between the ctools and
    gammalib versions. Please make sure that you have the corresponding gammalib
-   version installed before installing ctools. The Mac OS X binary packages
+   version installed before installing ctools. The Mac OS binary packages
    comprise both ctools and gammalib.
 
 ..
@@ -22,7 +22,10 @@ learn more about new features and corrected bugs in a given release.
 
     * - ctools
       - gammalib
-      - Mac OS X (10.7+) binary disk image
+      - Mac OS (10.7+) binary disk image
+    * - `1.7.3 <http://cta.irap.omp.eu/ctools/releases/ctools/ctools-1.7.3.tar.gz>`_
+      - `1.7.3 <http://cta.irap.omp.eu/ctools/releases/gammalib/gammalib-1.7.3.tar.gz>`_
+      - `ctools-1.7.3-macosx10.7.dmg <http://cta.irap.omp.eu/ctools/releases/ctools/ctools-1.7.3-macosx10.7.dmg>`_
     * - `1.7.2 <http://cta.irap.omp.eu/ctools/releases/ctools/ctools-1.7.2.tar.gz>`_
       - `1.7.2 <http://cta.irap.omp.eu/ctools/releases/gammalib/gammalib-1.7.2.tar.gz>`_
       - `ctools-1.7.2-macosx10.7.dmg <http://cta.irap.omp.eu/ctools/releases/ctools/ctools-1.7.2-macosx10.7.dmg>`_
diff --git a/doc/source/admin/install_binary.rst b/doc/source/admin/install_binary.rst
index 21c7856..b0d1523 100644
--- a/doc/source/admin/install_binary.rst
+++ b/doc/source/admin/install_binary.rst
@@ -3,15 +3,15 @@
 Installing as binary package
 ============================
 
-Mac OS X
---------
+Mac OS
+------
 
-After :ref:`downloading the Mac OS X binary disk image <sec_download>`
+After :ref:`downloading the Mac OS binary disk image <sec_download>`
 double-click on the image to mount the disk
 
 .. image:: macosx-disk-image.jpg
    :height: 300px
-   :alt: Mac OS X binary disk image
+   :alt: Mac OS binary disk image
    :align: center
 
 Now open the installer package by right-clicking (ctrl-click) on the installer
diff --git a/doc/source/admin/install_devel.rst b/doc/source/admin/install_devel.rst
index 6a1d539..3a7695d 100644
--- a/doc/source/admin/install_devel.rst
+++ b/doc/source/admin/install_devel.rst
@@ -3,36 +3,36 @@
 Installing the development version
 ==================================
 
-The current development version of the code can be downloaded as source
-tarballs, Mac OS X binaries, or directly from the `Git <https://git-scm.com/>`_
-repository.
+Alternatively to stable releases you can also install the development version
+of the code which includes the latest features that will become available
+with the next stable release. Installing the development version is recommended if
+you want to use latest code features and if you cannot wait for the next
+stable release. The current ctools development release is ``ctools-2.0.0.dev``.
 
-The current ctools development release is ``ctools-2.0.0.dev``.
+Installing the development version is also necessary **if you want to contribute
+to code development. In that case please follow the instructions on**
+:ref:`using_git` **and ignore the rest of this page.**
 
 
-Source tarballs
----------------
-
-Download the source tarballs from the following links
-
-- `ctools <http://cta.irap.omp.eu/ctools/releases/ctools/ctools-2.0.0.dev.tar.gz>`_
-- `GammaLib <http://cta.irap.omp.eu/ctools/releases/gammalib/gammalib-2.0.0.dev.tar.gz>`_
-
-and follow the instructions on :ref:`sec_install_source`.
+Getting the development version
+-------------------------------
 
+The first step is to get the development version of the code. There are three
+options for that first step: either get the source tarball or clone the
+source code from the `Git <https://git-scm.com/>`_ repository or download
+the binary installers for Mac OS.
 
-Binary packages
----------------
 
-Download the installer image from the following link
+Getting the source tarball
+~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-- `Mac OS X (10.7+) <http://cta.irap.omp.eu/ctools/releases/ctools/ctools-2.0.0.dev-macosx10.7.dmg>`_
-
-and follow the instructions on :ref:`sec_install_binary`.
+Download the source tarballs from the following links
 
+- `ctools <http://cta.irap.omp.eu/ctools/releases/ctools/ctools-2.0.0.dev.tar.gz>`_
+- `GammaLib <http://cta.irap.omp.eu/ctools/releases/gammalib/gammalib-2.0.0.dev.tar.gz>`_
 
-Git repository
---------------
+Cloning the Git repository
+~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 To clone the gammalib and ctools source codes, type
 
@@ -55,19 +55,52 @@ or
 
    $ git config --global http.sslverify "false"
 
-before retrieving the code.
-Before you will be able to compile the code you need to generate the
-configuration file using the ``autogen.sh`` script.
-Also make sure that you're actually on the devel branch of the git
-repository. GammaLib and ctools can be compiled and configured using
-the following command sequence (the code will be installed into the 
-``/usr/local/gamma`` directory):
+before retrieving the code. Before you will be able to compile the code directly
+you need to generate the configuration file using the ``autogen.sh`` script.
+Also make sure that you're actually on the devel branch of the git repository.
+You do this by typing:
 
 .. code-block:: bash
 
    $ cd gammalib
    $ git checkout devel
    $ ./autogen.sh
+   $ cd ../ctools
+   $ git checkout devel
+   $ ./autogen.sh
+
+
+Downloading Mac OS binary packages
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+You can download the Mac OS installer image from the following link
+
+- `Mac OS (10.7+) <http://cta.irap.omp.eu/ctools/releases/ctools/ctools-2.0.0.dev-macosx10.7.dmg>`_
+
+and follow the instructions on :ref:`sec_install_binary`.
+
+
+Compiling the development version
+---------------------------------
+
+The second step is to compile the development version. You do not need to
+compile the code in case that you installed the Mac OS binary packages.
+
+For code compilation, you can either compile the code directly using ``make``
+or you can build a conda package. The latter is preferred if you want to use
+ctools in a conda environment. We do not recommend to compile the development
+version directly against a conda version of Python.
+
+
+Compiling the development version
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+ctools and GammaLib can be compiled and configured using the following sequence
+of commands (the code will be installed into the ``/usr/local/gamma`` directory):
+
+.. code-block:: bash
+
+   $ cd gammalib
    $ ./configure
    $ make
    $ make check
@@ -75,8 +108,6 @@ the following command sequence (the code will be installed into the
    $ export GAMMALIB=/usr/local/gamma
    $ source $GAMMALIB/bin/gammalib-init.sh
    $ cd ../ctools
-   $ git checkout devel
-   $ ./autogen.sh
    $ ./configure
    $ make
    $ make check
@@ -93,34 +124,21 @@ on how to install ctools.
    not stored in the Git repository but are built using
    `swig <http://www.swig.org/>`_ from interface files located in the
    pyext folder. However, you do not need `swig <http://www.swig.org/>`_
-   when fetching a release as the Python wrappers are bundled with the
-   release tarballs.
+   when fetching a tarball as the Python wrappers are bundled with the
+   tarballs.
 
+Building a conda package
+~~~~~~~~~~~~~~~~~~~~~~~~
 
-Making a conda package
-----------------------
-
-To create a conda package for the development version, clone the gammalib and
-ctools source codes using
-
-.. code-block:: bash
-
-   $ git clone https://cta-gitlab.irap.omp.eu/gammalib/gammalib.git
-   $ git clone https://cta-gitlab.irap.omp.eu/ctools/ctools.git
-
-and type the following to create the conda packages (make sure that anaconda is
-included in your ``$PATH`` environment):
+Alternatively you can create a conda package using the following sequence
+of commands (make sure that anaconda is included in your ``$PATH`` environment):
 
 .. code-block:: bash
 
    $ cd gammalib
-   $ git checkout devel
-   $ ./autogen.sh
    $ ./configure
    $ conda-build dev/conda.recipe
    $ cd ../ctools
-   $ git checkout devel
-   $ ./autogen.sh
    $ ./configure
    $ conda-build dev/conda.recipe
 
@@ -133,6 +151,11 @@ version as follows:
    $ source activate ctools-devel
    $ conda install --use-local ctools=2.0.0.dev
 
-Note that you can choose between Python 2.7, 3.5, 3.6, 3.7 and 3.8 for your
-conda environment.
+Note that you can choose between Python 2.7, 3.5, 3.6, 3.7, 3.8 and 3.9 for
+your conda environment. If you only need the conda package for one specific
+Python version you can build the conda package as follows:
+
+.. code-block:: bash
+
+   $ conda-build dev/conda.recipe --python 3.6
 
diff --git a/doc/source/admin/release_history/1.7.3.rst b/doc/source/admin/release_history/1.7.3.rst
new file mode 100644
index 0000000..48fee06
--- /dev/null
+++ b/doc/source/admin/release_history/1.7.3.rst
@@ -0,0 +1,14 @@
+.. _1.7.3:
+
+ctools 1.7.3 release (2 December 2020)
+======================================
+
+Overview
+--------
+
+ctools 1.7.3 is a bug fix release for ctools release 1.7.
+
+The following bugs were fixed:
+
+* [`3423 <https://cta-redmine.irap.omp.eu/issues/3423>`_] -
+  Import matplotlib first in example scripts
diff --git a/doc/source/admin/release_history/index.rst b/doc/source/admin/release_history/index.rst
index a43b852..5149ff4 100755
--- a/doc/source/admin/release_history/index.rst
+++ b/doc/source/admin/release_history/index.rst
@@ -7,6 +7,7 @@ Release History
    :maxdepth: 1
 
    ctools 2.0 <2.0>
+   ctools 1.7.3 <1.7.3>
    ctools 1.7.2 <1.7.2>
    ctools 1.7.1 <1.7.1>
    ctools 1.7 <1.7>
diff --git a/examples/show_butterfly.py b/examples/show_butterfly.py
index 61fabc7..70eeb43 100755
--- a/examples/show_butterfly.py
+++ b/examples/show_butterfly.py
@@ -2,7 +2,7 @@
 # ==========================================================================
 # Shows butterfly diagram created with ctbutterfly
 #
-# Copyright (C) 2014-2019 Michael Mayer
+# Copyright (C) 2014-2020 Michael Mayer
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -19,8 +19,6 @@
 #
 # ==========================================================================
 import sys
-import gammalib
-import cscripts
 try:
     import matplotlib.pyplot as plt
     plt.figure()
@@ -28,6 +26,8 @@ try:
 except (ImportError, RuntimeError):
     print('This script needs the "matplotlib" module')
     sys.exit()
+import gammalib
+import cscripts
 
 
 # ======================================== #
diff --git a/examples/show_irf.py b/examples/show_irf.py
index 7698fb5..3faecbb 100755
--- a/examples/show_irf.py
+++ b/examples/show_irf.py
@@ -2,7 +2,7 @@
 # ==========================================================================
 # Display Instrument Response Function
 #
-# Copyright (C) 2017-2018 Juergen Knoedlseder
+# Copyright (C) 2017-2020 Juergen Knoedlseder
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -20,8 +20,6 @@
 # ==========================================================================
 import sys
 import math
-import gammalib
-import cscripts
 try:
     import matplotlib.pyplot as plt
     from matplotlib import ticker
@@ -31,6 +29,8 @@ try:
 except (ImportError, RuntimeError):
     print('This script needs the "matplotlib" module')
     sys.exit()
+import gammalib
+import cscripts
 
 
 # ========= #
diff --git a/examples/show_lightcurve.py b/examples/show_lightcurve.py
index 501707f..1020749 100755
--- a/examples/show_lightcurve.py
+++ b/examples/show_lightcurve.py
@@ -2,7 +2,7 @@
 # ==========================================================================
 # Display lightcurve generated by cslightcrv
 #
-# Copyright (C) 2017 Juergen Knoedlseder
+# Copyright (C) 2017-2020 Juergen Knoedlseder
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -19,8 +19,6 @@
 #
 # ==========================================================================
 import sys
-import gammalib
-import cscripts
 try:
     import matplotlib.pyplot as plt
     plt.figure()
@@ -28,6 +26,8 @@ try:
 except (ImportError, RuntimeError):
     print('This script needs the "matplotlib" module')
     sys.exit()
+import gammalib
+import cscripts
 
 
 # =============== #
diff --git a/examples/show_model.py b/examples/show_model.py
index b57531d..306a5f4 100755
--- a/examples/show_model.py
+++ b/examples/show_model.py
@@ -2,7 +2,7 @@
 # ==========================================================================
 # Shows the photon spectrum of a model
 #
-# Copyright (C) 2015-2016 Juergen Knoedlseder
+# Copyright (C) 2015-2020 Juergen Knoedlseder
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -19,8 +19,6 @@
 #
 # ==========================================================================
 import sys
-import gammalib
-import cscripts
 try:
     import matplotlib.pyplot as plt
     plt.figure()
@@ -28,6 +26,8 @@ try:
 except (ImportError, RuntimeError):
     print('This script needs the "matplotlib" module')
     sys.exit()
+import gammalib
+import cscripts
 
 
 # ======================= #
diff --git a/examples/show_obs.py b/examples/show_obs.py
index 1cb6de7..fe1a174 100755
--- a/examples/show_obs.py
+++ b/examples/show_obs.py
@@ -2,7 +2,7 @@
 # ==========================================================================
 # Display summary of observation definition XML file
 #
-# Copyright (C) 2016 Michael Mayer
+# Copyright (C) 2016-2020 Michael Mayer
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -19,8 +19,6 @@
 #
 # ==========================================================================
 import sys
-import gammalib
-import cscripts
 try:
     import matplotlib.pyplot as plt
     plt.figure()
@@ -28,6 +26,8 @@ try:
 except (ImportError, RuntimeError):
     print('This script needs the "matplotlib" module')
     sys.exit()
+import gammalib
+import cscripts
 
 
 # ==================== #
diff --git a/examples/show_pha.py b/examples/show_pha.py
index 7aa2404..b862fb8 100755
--- a/examples/show_pha.py
+++ b/examples/show_pha.py
@@ -2,7 +2,7 @@
 # ==========================================================================
 # Show a spectrum in PHA format
 #
-# Copyright (C) 2013-2016 Juergen Knoedlseder
+# Copyright (C) 2013-2020 Juergen Knoedlseder
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -20,8 +20,6 @@
 # ==========================================================================
 import sys
 import math
-import gammalib
-import cscripts
 try:
     import matplotlib.pyplot as plt
     plt.figure()
@@ -29,6 +27,8 @@ try:
 except (ImportError, RuntimeError):
     print('This script needs the "matplotlib" module')
     sys.exit()
+import gammalib
+import cscripts
 
 
 # ================= #
diff --git a/examples/show_phases.py b/examples/show_phases.py
index f7c58ee..476636d 100755
--- a/examples/show_phases.py
+++ b/examples/show_phases.py
@@ -2,7 +2,7 @@
 # ==========================================================================
 # Display phase information from event list
 #
-# Copyright (C) 2017 Juergen Knoedlseder
+# Copyright (C) 2017-2020 Juergen Knoedlseder
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -19,8 +19,6 @@
 #
 # ==========================================================================
 import sys
-import gammalib
-import cscripts
 try:
     import matplotlib.pyplot as plt
     plt.figure()
@@ -28,6 +26,8 @@ try:
 except (ImportError, RuntimeError):
     print('This script needs the "matplotlib" module')
     sys.exit()
+import gammalib
+import cscripts
 
 
 # =========== #
diff --git a/examples/show_pointings.py b/examples/show_pointings.py
index 02c4b96..7db62a7 100755
--- a/examples/show_pointings.py
+++ b/examples/show_pointings.py
@@ -2,7 +2,7 @@
 # ==========================================================================
 # Display pointings in observation definition XML file
 #
-# Copyright (C) 2017 Juergen Knoedlseder
+# Copyright (C) 2017-2020 Juergen Knoedlseder
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -19,8 +19,6 @@
 #
 # ==========================================================================
 import sys
-import gammalib
-import cscripts
 try:
     import matplotlib.pyplot as plt
     plt.figure()
@@ -28,6 +26,8 @@ try:
 except (ImportError, RuntimeError):
     print('This script needs the "matplotlib" module')
     sys.exit()
+import gammalib
+import cscripts
 
 
 # =============================== #
diff --git a/examples/show_pull_evolution.py b/examples/show_pull_evolution.py
index 4920388..ba9cf40 100755
--- a/examples/show_pull_evolution.py
+++ b/examples/show_pull_evolution.py
@@ -2,7 +2,7 @@
 # ==========================================================================
 # Shows the evolution of the mean and rms pull
 #
-# Copyright (C) 2015-2017 Juergen Knoedlseder
+# Copyright (C) 2015-2020 Juergen Knoedlseder
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -19,7 +19,6 @@
 #
 # ==========================================================================
 import sys
-import cscripts
 try:
     import matplotlib.pyplot as plt
     plt.figure()
@@ -32,6 +31,7 @@ try:
 except ImportError:
     print('This script needs the "numpy" module')
     sys.exit()
+import cscripts
 
 
 # =================== #
diff --git a/examples/show_pull_histogram.py b/examples/show_pull_histogram.py
index 57d96bb..e90fb82 100755
--- a/examples/show_pull_histogram.py
+++ b/examples/show_pull_histogram.py
@@ -2,7 +2,7 @@
 # ==========================================================================
 # Shows the pull histogram
 #
-# Copyright (C) 2011-2017 Juergen Knoedlseder
+# Copyright (C) 2011-2020 Juergen Knoedlseder
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -19,7 +19,6 @@
 #
 # ==========================================================================
 import sys
-import cscripts
 try:
     import matplotlib.pyplot as plt
     plt.figure()
@@ -32,6 +31,7 @@ try:
 except ImportError:
     print('This script needs the "numpy" module')
     sys.exit()
+import cscripts
 
 
 # =================== #
diff --git a/examples/show_residuals.py b/examples/show_residuals.py
index c992f42..2042e11 100755
--- a/examples/show_residuals.py
+++ b/examples/show_residuals.py
@@ -2,7 +2,7 @@
 # ==========================================================================
 # Display residuals generated by csresspec
 #
-# Copyright (C) 2017-2019 Luigi Tibaldo
+# Copyright (C) 2017-2020 Luigi Tibaldo
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -20,8 +20,6 @@
 # ==========================================================================
 import sys
 import math
-import gammalib
-import cscripts
 try:
     import matplotlib.pyplot as plt
     plt.figure()
@@ -29,6 +27,8 @@ try:
 except (ImportError, RuntimeError):
     print('This script needs the "matplotlib" module')
     sys.exit()
+import gammalib
+import cscripts
 
 
 # ======================= #
diff --git a/examples/show_response.py b/examples/show_response.py
index bc7290b..9d6b422 100755
--- a/examples/show_response.py
+++ b/examples/show_response.py
@@ -2,7 +2,7 @@
 # ==========================================================================
 # Shows one or several CTA response functions.
 #
-# Copyright (C) 2014-2017 Juergen Knoedlseder
+# Copyright (C) 2014-2020 Juergen Knoedlseder
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -20,8 +20,6 @@
 # ==========================================================================
 import sys
 import math
-import gammalib
-import cscripts
 try:
     import matplotlib.pyplot as plt
     plt.figure()
@@ -29,6 +27,8 @@ try:
 except (ImportError, RuntimeError):
     print('This script needs the "matplotlib" module')
     sys.exit()
+import gammalib
+import cscripts
 
 
 # ================================== #
diff --git a/examples/show_rmf.py b/examples/show_rmf.py
index 83479db..7790e97 100755
--- a/examples/show_rmf.py
+++ b/examples/show_rmf.py
@@ -2,7 +2,7 @@
 # ==========================================================================
 # Display Redistribution Matrix File
 #
-# Copyright (C) 2018-2019 Juergen Knoedlseder
+# Copyright (C) 2018-2020 Juergen Knoedlseder
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -19,8 +19,6 @@
 #
 # ==========================================================================
 import sys
-import gammalib
-import cscripts
 try:
     import matplotlib.pyplot as plt
     plt.figure()
@@ -28,6 +26,8 @@ try:
 except (ImportError, RuntimeError):
     print('This script needs the "matplotlib" module')
     sys.exit()
+import gammalib
+import cscripts
 
 
 # ======== #
diff --git a/examples/show_sensitivity.py b/examples/show_sensitivity.py
index 7aea2c1..ff4b94c 100755
--- a/examples/show_sensitivity.py
+++ b/examples/show_sensitivity.py
@@ -2,7 +2,7 @@
 # ==========================================================================
 # Display differential sensitivity plot generated by cssens
 #
-# Copyright (C) 2015-2017 Juergen Knoedlseder
+# Copyright (C) 2015-2020 Juergen Knoedlseder
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -20,8 +20,6 @@
 # ==========================================================================
 import sys
 import math
-import gammalib
-import cscripts
 try:
     import matplotlib.pyplot as plt
     plt.figure()
@@ -29,6 +27,8 @@ try:
 except (ImportError, RuntimeError):
     print('This script needs the "matplotlib" module')
     sys.exit()
+import gammalib
+import cscripts
 
 
 # ===================== #
diff --git a/examples/show_significance_distribution.py b/examples/show_significance_distribution.py
index 20d88af..3bcdefd 100755
--- a/examples/show_significance_distribution.py
+++ b/examples/show_significance_distribution.py
@@ -2,7 +2,7 @@
 # ==========================================================================
 # Shows the distribution of significances in a given significance map.
 #
-# Copyright (C) 2018-2019 Andreas Specovius
+# Copyright (C) 2018-2020 Andreas Specovius
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -46,8 +46,6 @@
 # ==========================================================================
 import sys
 import math
-import gammalib
-import cscripts
 try:
     import matplotlib.pyplot as plt
     plt.figure()
@@ -60,6 +58,8 @@ try:
 except ImportError:
     print('This script needs the "numpy" module')
     sys.exit()
+import gammalib
+import cscripts
 
 
 # ======================= #
diff --git a/examples/show_spectrum.py b/examples/show_spectrum.py
index a199795..0b91071 100755
--- a/examples/show_spectrum.py
+++ b/examples/show_spectrum.py
@@ -19,8 +19,6 @@
 #
 # ==========================================================================
 import sys
-import gammalib
-import cscripts
 try:
     import matplotlib.pyplot as plt
     plt.figure()
@@ -33,6 +31,8 @@ try:
 except ImportError:
     print('This script needs the "numpy" module')
     sys.exit()
+import gammalib
+import cscripts
 
 
 # ===================================== #
diff --git a/examples/show_ts_distribution.py b/examples/show_ts_distribution.py
index 0a89da8..5bf4998 100755
--- a/examples/show_ts_distribution.py
+++ b/examples/show_ts_distribution.py
@@ -2,7 +2,7 @@
 # ==========================================================================
 # Display TS distribution generated by cstsdist
 #
-# Copyright (C) 2011-2017 Jurgen Knodlseder
+# Copyright (C) 2011-2020 Jurgen Knodlseder
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -21,7 +21,6 @@
 import sys
 import csv
 import math
-import cscripts
 try:
     import matplotlib.pyplot as plt
     plt.figure()
@@ -34,6 +33,7 @@ try:
 except ImportError:
     print('This script needs the "numpy" module')
     sys.exit()
+import cscripts
 
 
 # ==================== #
diff --git a/examples/show_variability_evolution.py b/examples/show_variability_evolution.py
index e1adfc8..811b088 100755
--- a/examples/show_variability_evolution.py
+++ b/examples/show_variability_evolution.py
@@ -2,7 +2,7 @@
 # ==========================================================================
 # Shows source variability evolution created with ctfindvar
 #
-# Copyright (C) 2018 Simon Bonnefoy
+# Copyright (C) 2018-2020 Simon Bonnefoy
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -19,8 +19,6 @@
 #
 # ==========================================================================
 import sys
-import gammalib
-import cscripts
 try:
     import matplotlib.pyplot as plt
     plt.figure()
@@ -28,6 +26,8 @@ try:
 except (ImportError, RuntimeError):
     print('This script needs the "matplotlib" module')
     sys.exit()
+import gammalib
+import cscripts
 
 
 # ========================== #
diff --git a/examples/show_viscube.py b/examples/show_viscube.py
index 6f9d711..9ed14ed 100755
--- a/examples/show_viscube.py
+++ b/examples/show_viscube.py
@@ -2,7 +2,7 @@
 # ==========================================================================
 # Show visibility cube
 #
-# Copyright (C) 2019 Juergen Knoedlseder
+# Copyright (C) 2019-2020 Juergen Knoedlseder
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -19,8 +19,6 @@
 #
 # ==========================================================================
 import sys
-import gammalib
-import cscripts
 try:
     import matplotlib.pyplot as plt
     plt.figure()
@@ -28,6 +26,8 @@ try:
 except (ImportError, RuntimeError):
     print('This script needs the "matplotlib" module')
     sys.exit()
+import gammalib
+import cscripts
 
 
 # =========================== #