Here's a simple Tool for Cheetah templating:

import cherrypy as cp

class CheetahHandler(cp.dispatch.LateParamPageHandler):
    def __init__(self, template, next_handler):
        self.template = template
        self.next_handler = next_handler
    
    def __call__(self):
        env = globals().copy()
        env.update(self.next_handler())
        tmpl = getattr(__import__(self.template, globals(), locals(), [self.template], -1), self.template)
        return str(tmpl(searchList=[env]))

class CheetahLoader(object):
    def __call__(self, template):
        cp.request.handler = CheetahHandler(template, cp.request.handler)

main = CheetahLoader()
cp.tools.cheetah = cp.Tool('on_start_resource', main)

Use it like this:

class Test_Cheetah_Tool(object):
    @cp.expose
    @cp.tools.cheetah(template='Greetings')
    def index(self, username=None, **kwargs):
        return {'username': username}

Greetings.tmpl:

Hello, $username!

Compile with:

cheetah compile Greetings.tmpl