Read contents of .gz file with python - gzip

Question

I'm new to Python and am running into issues reading the contents of a .gz file:
I've got a folder full of .gz files that I've extracted programatically using a private API. The contents of each .gz file is a .xml file so I need to iterate over the dir and extract them.
The problem is when I programatically extract these .gz files into their respective .xml versions... The files create without error and when I open one (Using TextWrangler) it looks like a regular .xml file, but NOT when I view it in a hex editor. Also, when I open the .xml file programatically and print it's contents, it shows up as a bunch of (binary?) jumbled text.
With the above in mind, If I manually extract one of the files (ie: using OSX, but not Python), the file is viewable in a hex editor as I'd expect it to be.
Here is my code snippet (appropriate imports not shown, but they are glob and gzip):
searchpattern = siteid + "_" + resource + "_*.gz"
for infile in glob.glob(workingDir + searchpattern):
print infile
#read the zipped contents (https://docs.python.org/2/library/gzip.html)
f = gzip.open(infile, 'rb')
file_content = f.read()
file_content = str(file_content) #This was an attempt to fix
print file_content # This shows a bunch of mumbo jumbo
#write the contents we just read to a new file (uncompressed)
newfilename = infile[0:-3] # the filename without the ".gz"
newfilename = newfilename + ".xml"
fnew = open(newfilename, 'w+b')
fnew.write(str(file_content))
fnew.close()
#delete the .gz version of the file
#os.remove(infile)

Answer 1

If I run this against XML I don't get any issues with the program.
If I compress and XML and extract it with this program and diff the original with the output of this program I get no differences.
This program does add an extra ".xml" extension.

Answer 2

So this turns out to be a silly mistake on my part, but I'll post this as a followup for anybody else who makes the same mistake I did.
The problem was that i was zipping what had already been zipped earlier in my program. So with that in mind, my code snippet on this thread didn't have anything wrong with it. Neither did my code that i created the .gz file with (technically). As you can see below. Opening the file normally, instead of with the gzip library earlier in the program did the trick.
#Download and write the contents of each response to a .gz file
if limitCounter < limit or int(limit) == 0:
print _name + " " + scopeStartDate + " through " + scopeEndDate + " at " + href
file = api.get(href)
gz_file_content = file.content
#gz_file = gzip.open(workingDir + _name, "wb") # This breaks the program later
gz_file = open(workingDir + _name, 'wb') # This works.
gz_file.write(gz_file_content)
gz_file.close()