Creating a list of files in a directory

[Jeff Klassen]

Hello,

I am new to Python. As a non-programmer I am encouraged by the level of
'success' I feel I have had, relative to similar learning attempts in other
languages.

I would like to simply do the following:
- read all of files of a particular form (e.g. *.cev) from a particular
directory
- manipulate them with a series of re.sub expressions
- write each file to its own output file with a certain form (e.g. *.out).

I have been able to create the re stuff, and process individual files.
However, I cannot get a for loop to do everything in a directory.

Here is the code I came up with. (I am wanting to create a list of all files
that conform to *.cev)

----------------------------
import dircache
import re

workingdir=dircache.listdir('/jobs/python/learning/')
filespec = re.compile(r'.*?\.cev')
filestoprocess = []

for allfiles in workingdir:
    matchedfile=filespec.match(allfiles)
    filestoprocess.append(matchedfile.group())

print filestoprocess
----------------------------

When I run this script I am returned:
AttributeError: 'None' object has no attribute 'group'

When I issue these commands in the Python Shell, substituting an actual
value for allfiles such as 'mat.cev', everything works OK. I can execute
filestoprocess.append(matchedfile.group()) and then print filestoprocess,
and I am returned ['mat.cev']. Why does this fail to work inside of the
loop?

Thanks very much for any help.

Jeff