make headers more compact

doc/src/Python_call.rst

@@ -1,5 +1,5 @@
-Calling Python from a LAMMPS input script
-*****************************************
+Calling Python from LAMMPS
+**************************
 
 LAMMPS has several commands which can be used to invoke Python
 code directly from an input script:

doc/src/Python_error.rst

@@ -1,4 +1,4 @@
-LAMMPS error handling in Python
+Handling LAMMPS errors
 *******************************
 
 Compiling the shared library with :ref:`C++ exception support <exceptions>` provides a better error

doc/src/Python_examples.rst

@@ -1,10 +1,10 @@
-Example Python scripts that use LAMMPS
-======================================
+Example Python scripts
+======================
 
-The python/examples directory has Python scripts which show how Python
+The ``python/examples`` directory has Python scripts which show how Python
 can run LAMMPS, grab data, change it, and put it back into LAMMPS.
 
-These are the Python scripts included as demos in the python/examples
+These are the Python scripts included as demos in the ``python/examples``
 directory of the LAMMPS distribution, to illustrate the kinds of
 things that are possible when Python wraps LAMMPS.  If you create your
 own scripts, send them to us and we can include them in the LAMMPS
@@ -32,7 +32,7 @@ distribution.
 
 ----------
 
-For the viz_tool.py and vizplotgui_tool.py commands, replace "tool"
+For the ``viz_tool.py`` and ``vizplotgui_tool.py`` commands, replace "tool"
 with "gl" or "atomeye" or "pymol" or "vmd", depending on what
 visualization package you have installed.
 

doc/src/Python_ext.rst

@@ -1,10 +1,10 @@
-Extending the library and Python interface
+Extending the Python interface
 ******************************************
 
-As noted previously, the Python class methods correspond one-to-one with
-the functions in the LAMMPS library interface in ``src/library.cpp`` and
-``library.h``.  This means you can extend the Python wrapper by
-following these steps:
+As noted previously, most of the :py:class:`lammps <lammps.lammps>`
+Python class methods correspond one-to-one with the functions in the
+LAMMPS library interface in ``src/library.cpp`` and ``library.h``.
+This means you can extend the Python wrapper by following these steps:
 
 * Add a new interface function to ``src/library.cpp`` and
   ``src/library.h``.
@@ -17,3 +17,4 @@ following these steps:
 * You should now be able to invoke the new interface function from a
   Python script.
 
+