How to pass variables from python script to bash script

I would print it to a file chosen on the command line then I'd get that value in bash with something like cat.

So you'd go:

python b.py tempfile.txt
var=`cat tempfile.txt`
rm tempfile.txt

[EDIT, another idea based on other answers]

Your other option is to format your output carefully so you can use bash functions like head/tail to pipe only the first/last lines into your next program.

I believe the answer is

.py

import sys 
a=['zero','one','two','three'] 
b = int(sys.argv[1]) 
###your python script can still print to stderr if it likes to 
print >> sys.stderr, "I am no converting" 
result = a[b] 
print result

.sh

#!/bin/sh 

num=2 
text=`python numtotext.py $num` 
echo "$num as text is $text"