How can I create a GzipFile instance from the “file-like object” that urllib.urlopen() returns?

The urlopen docs list the supported methods of the object that is returned. I recommend wrapping the object in another class that supports the methods that gzip expects.

Other option: call the read method of the response object and put the result in a StringIO object (which should support all methods that gzip expects). This maybe a little more expensive though.

E.g.

import gzip
import json
import StringIO
import urllib

url = urllib.urlopen('http://api.stackoverflow.com/1.0/badges/name')
url_f = StringIO.StringIO(url.read())
g = gzip.GzipFile(fileobj=url_f)
j = json.load(g)

import urllib2
import json
import gzip
import io

url='http://api.stackoverflow.com/1.0/badges/name'
page=urllib2.urlopen(url)
gzip_filehandle=gzip.GzipFile(fileobj=io.BytesIO(page.read()))
json_data=json.loads(gzip_filehandle.read())
print(json_data)

io.BytesIO is for Python2.6+. For older versions of Python, you could use cStringIO.StringIO.