Python urlparse how to edit parameter values?

[madlax]

I have a long list of URL's that I need my Python script to iterate through. I need it to replace the parameter values in the URL with a certain string, and keep the parameter names the same.
But I have encounted a bit of a problem:

from urlparse import urlparse
urls = open("/path/to/urls.txt", "r").readlines()
for url in urls:
    addr = urlparse(url)

addr then contains something like this:

ParseResult(scheme='http', netloc='www.example.com', path='/path/to/file.php', params='', query='param1=value1&param2=value2&parm3=value3', fragment='')

addr.query contains this:

param1=value1&param2=value2&parm3=value3

I would like to replace all the parameter values ( in this case value1, value2 and value3) with a certain string, the same string for each of them.

The problem is urlparse squishes both the parameter names and thier values into the same element in a list, so its not so easy to automate replacing the parameter values with a string, while keeping the names the same. Anyone know how I can do this? I would appreciate any help on this, thank you.

[bvdet]

Could you provide a sample of the URLs you are trying to parse and what the modified URLs are supposed to look like?

[dwblas]

You may be able to split on the "&, change the string, and "&".join() etc.

[Glenton]

Regular expressions would be a good way to do it.