Improve highlighting of some code blocks. (GH-6401)

Doc/using/cmdline.rst

@@ -178,11 +178,15 @@ Generic options
 .. cmdoption:: -V
                --version
 
-   Print the Python version number and exit.  Example output could be::
+   Print the Python version number and exit.  Example output could be:
+
+   .. code-block:: none
 
        Python 3.6.0b2+
 
-   When given twice, print more information about the build, like::
+   When given twice, print more information about the build, like:
+
+   .. code-block:: none
 
        Python 3.6.0b2+ (3.6:84a3c5003510+, Oct 26 2016, 02:33:55)
        [GCC 6.2.0 20161005]
@@ -355,7 +359,9 @@ Miscellaneous options
 
    Warning control.  Python's warning machinery by default prints warning
    messages to :data:`sys.stderr`.  A typical warning message has the following
-   form::
+   form:
+
+   .. code-block:: none
 
        file:line: category: message
 

Doc/using/unix.rst

@@ -118,7 +118,9 @@ Miscellaneous
 =============
 
 To easily use Python scripts on Unix, you need to make them executable,
-e.g. with ::
+e.g. with
+
+.. code-block:: shell-session
 
    $ chmod +x script
 

Doc/using/windows.rst

@@ -210,7 +210,9 @@ The options listed above can also be provided in a file named ``unattend.xml``
 alongside the executable. This file specifies a list of options and values.
 When a value is provided as an attribute, it will be converted to a number if
 possible. Values provided as element text are always left as strings. This
-example file sets the same options and the previous example::
+example file sets the same options and the previous example:
+
+.. code-block:: xml
 
     <Options>
         <Option Name="InstallAllUsers" Value="no" />
@@ -343,7 +345,9 @@ Windows allows environment variables to be configured permanently at both the
 User level and the System level, or temporarily in a command prompt.
 
 To temporarily set environment variables, open Command Prompt and use the
-:command:`set` command::
+:command:`set` command:
+
+.. code-block:: doscon
 
     C:\>set PATH=C:\Program Files\Python 3.6;%PATH%
     C:\>set PYTHONPATH=%PYTHONPATH%;C:\My_python_lib
@@ -503,7 +507,7 @@ From a script
 Let's create a test Python script - create a file called ``hello.py`` with the
 following contents
 
-::
+.. code-block:: python
 
     #! python
     import sys
@@ -518,7 +522,7 @@ From the directory in which hello.py lives, execute the command:
 You should notice the version number of your latest Python 2.x installation
 is printed.  Now try changing the first line to be:
 
-::
+.. code-block:: python
 
     #! python3
 
@@ -566,7 +570,7 @@ which interpreter to use.  The supported virtual commands are:
 
 For example, if the first line of your script starts with
 
-::
+.. code-block:: sh
 
   #! /usr/bin/python
 
@@ -592,7 +596,7 @@ Arguments in shebang lines
 The shebang lines can also specify additional options to be passed to the
 Python interpreter.  For example, if you have a shebang line:
 
-::
+.. code-block:: sh
 
   #! /usr/bin/python -v
 
@@ -683,7 +687,7 @@ For example:
 
 * Setting ``PY_PYTHON=3.1`` is equivalent to the INI file containing:
 
-::
+.. code-block:: ini
 
   [defaults]
   python=3.1
@@ -691,7 +695,7 @@ For example:
 * Setting ``PY_PYTHON=3`` and ``PY_PYTHON3=3.1`` is equivalent to the INI file
   containing:
 
-::
+.. code-block:: ini
 
   [defaults]
   python=3