newbie -- find replace help using csv file info

[ChrisP_Buffalo]

I'm trying to automate a series of find/replace actions. I have an input file containing a large list of stemmed verb forms like this:
apolog
apologis
becam
apologis
apologis
apologis
apologis
becom
becom
aris
arisen
arisen

I want to change every "apologis" to "apolog", every "arisen" to "aris" and so on. Since my set of changes is large, I created a csv file containing a list of old forms and new forms like this:
apologis,apolog
arisen,aris
author,authoris
beaten,beat
becom,becam
capitalis,capit
categoris,categor

Now I've written a script that I thought would iterate through each csv entry, and make replacements in the target file, but it just prints the original file with no changes. Here's my code:

import string, sys, os
from os.path import join
import csv

myFile = open("input.csv","r")
x = "".join(myFile)

changes = csv.reader(open('test2_stext_rtext.csv', 'rb'))

for old, new in changes:
        replaced_verb = x.replace(old, new)

print replaced_verb
myFile.close()

If I take this code and put a specific string in, it works (just for that string), like this:

for old, new in changes:
replaced_verb = x.replace('aplogis', 'aplog')

So the problem seems to be to get Python to take each old and new form properly. Any suggestions would be appreciated.

[bumsfeld]

Variable myFile is just file handle, what do you expect join() would do to it?

[ChrisP_Buffalo]

I expect it to take the file object “myFile” and turn it into a string object “x” so that the .replace method will work. Perhaps there is a better way to do this.