"Just do it"!-) Get pyparsing.py, e.g. from here, and put it in your app engine app's directory; now you can just import pyparsing
in your app code and use it.
For example, tweak the greeting.py from here to be:
from pyparsing import Word, alphas
greet = Word( alphas ) + "," + Word( alphas ) + "!" # <-- grammar defined here
hello = "Hello, World!"
print "Content-type: text/plain\n"
print hello, "->", greet.parseString( hello )
add to your app.yaml right under handlers:
the two lines:
- url: /parshello
script: greeting.py
start your app, visit http://localhost:8083/parshello
(or whatever port you're running on;-), and you'll see in your browser the plain text output:
Hello, World! -> ['Hello', ',', 'World', '!']