$ echo "$HOSTNAME"
c0a80165.tipt.aol.com
$ /usr/local/bin/python
Python 2.4.2 (#1, Dec 30 2005, 11:14:42) 
[GCC 4.0.1 (Apple Computer, Inc. build 5247)] on darwin
Type "help", "copyright", "credits" or "license" for
more information.
>>> import os.path
>>> os.path.expandvars("$HOME")
'/Users/dougfort'
>>> os.path.expandvars("$HOSTNAME")
'$HOSTNAME'
>>> 

arthurformat-d09:arthur$ echo $HOSTNAME
arthurformat-d09.ats.aol.com
arthurformat-d09:arthur$ /cm/tools/bin/python
Python 2.3.4 (#1, Jul 28 2004, 14:55:53) 
[GCC 3.3.1] on linux2
Type "help", "copyright", "credits" or "license" for
more information.
>>> import os.path
>>> os.path.expandvars("$HOME")
'/opt/aol/production/arthur'
>>> os.path.expandvars("$HOSTNAME")
'arthurformat-d09.ats.aol.com'