Simple URL GET/POST function in Python

You could use this to wrap urllib2:

def URLRequest(url, params, method="GET"):
    if method == "POST":
        return urllib2.Request(url, data=urllib.urlencode(params))
    else:
        return urllib2.Request(url + "?" + urllib.urlencode(params))

That will return a Request object that has result data and response codes.

import urllib

def fetch_thing(url, params, method):
    params = urllib.urlencode(params)
    if method=='POST':
        f = urllib.urlopen(url, params)
    else:
        f = urllib.urlopen(url+'?'+params)
    return (f.read(), f.code)


content, response_code = fetch_thing(
                              'http://google.com/', 
                              {'spam': 1, 'eggs': 2, 'bacon': 0}, 
                              'GET'
                         )

[Update]

Some of these answers are old. Today I would use the requests module like the answer by robaple.

Even easier: via the requests module.

import requests
get_response = requests.get(url='http://google.com')
post_data = {'username':'joeb', 'password':'foobar'}
# POST some form-encoded data:
post_response = requests.post(url='http://httpbin.org/post', data=post_data)

To send data that is not form-encoded, send it serialised as a string (example taken from the documentation):

import json
post_response = requests.post(url='http://httpbin.org/post', data=json.dumps(post_data))
# If using requests v2.4.2 or later, pass the dict via the json parameter and it will be encoded directly:
post_response = requests.post(url='http://httpbin.org/post', json=post_data)

requests

https://github.com/kennethreitz/requests/

Here's a few common ways to use it:

import requests
url = 'https://...'
payload = {'key1': 'value1', 'key2': 'value2'}

# GET
r = requests.get(url)

# GET with params in URL
r = requests.get(url, params=payload)

# POST with form-encoded data
r = requests.post(url, data=payload)

# POST with JSON 
import json
r = requests.post(url, data=json.dumps(payload))

# Response, status etc
r.text
r.status_code

httplib2

https://github.com/jcgregorio/httplib2

>>> from httplib2 import Http
>>> from urllib import urlencode
>>> h = Http()
>>> data = dict(name="Joe", comment="A test comment")
>>> resp, content = h.request("http://bitworking.org/news/223/Meet-Ares", "POST", urlencode(data))
>>> resp
{'status': '200', 'transfer-encoding': 'chunked', 'vary': 'Accept-Encoding,User-Agent',
 'server': 'Apache', 'connection': 'close', 'date': 'Tue, 31 Jul 2007 15:29:52 GMT', 
 'content-type': 'text/html'}