Just a short, simple one about the excellent Requests module for Python.

I can't seem to find in the documentation what the variable 'proxies' should contain. When I send it a dict with a standard "IP:PORT" value it rejected it asking for 2 values. So, I guess (because this doesn't seem to be covered in the docs) that the first value is the ip and the second the port?

The docs mention this only:

proxies – (optional) Dictionary mapping protocol to the URL of the proxy.

So I tried this... what should I be doing?

proxy = { ip: port}

and should I convert these to some type before putting them in the dict?

r = requests.get(url,headers=headers,proxies=proxy)

The proxies' dict syntax is {"protocol":"ip:port", ...}. With it you can specify different (or the same) proxie(s) for requests using http, https, and ftp protocols:

http_proxy  = "http://10.10.1.10:3128"
https_proxy = "https://10.10.1.11:1080"
ftp_proxy   = "ftp://10.10.1.10:3128"

proxyDict = {
              "http"  : http_proxy,
              "https" : https_proxy,
              "ftp"   : ftp_proxy
            }

r = requests.get(url, headers=headers, proxies=proxyDict)

Deduced from the requests documentation:

Parameters:
method – method for the new Request object.
url – URL for the new Request object.
...
proxies – (optional) Dictionary mapping protocol to the URL of the proxy.
...

On linux you can also do this via the HTTP_PROXY, HTTPS_PROXY, and FTP_PROXY environment variables:

export HTTP_PROXY=10.10.1.10:3128
export HTTPS_PROXY=10.10.1.11:1080
export FTP_PROXY=10.10.1.10:3128

On Windows:

set http_proxy=10.10.1.10:3128
set https_proxy=10.10.1.11:1080
set ftp_proxy=10.10.1.10:3128

Thanks, Jay for pointing this out:
The syntax changed with requests 2.0.0.
You'll need to add a schema to the url: http://docs.python-requests.org/en/latest/user/advanced/#proxies