Download and decompress gzipped file in memory?

For those using Python 3, the equivalent answer is:

import urllib.request
import io
import gzip

response = urllib.request.urlopen(FILE_URL)
compressed_file = io.BytesIO(response.read())
decompressed_file = gzip.GzipFile(fileobj=compressed_file)

with open(OUTFILE_PATH, 'wb') as outfile:
    outfile.write(decompressed_file.read())

You need to seek to the beginning of compressedFile after writing to it but before passing it to gzip.GzipFile(). Otherwise it will be read from the end by gzip module and will appear as an empty file to it. See below:

#! /usr/bin/env python
import urllib2
import StringIO
import gzip

baseURL = "https://www.kernel.org/pub/linux/docs/man-pages/"
filename = "man-pages-3.34.tar.gz"
outFilePath = "man-pages-3.34.tar"

response = urllib2.urlopen(baseURL + filename)
compressedFile = StringIO.StringIO()
compressedFile.write(response.read())
#
# Set the file's current position to the beginning
# of the file so that gzip.GzipFile can read
# its contents from the top.
#
compressedFile.seek(0)

decompressedFile = gzip.GzipFile(fileobj=compressedFile, mode='rb')

with open(outFilePath, 'w') as outfile:
    outfile.write(decompressedFile.read())