Determine the Python version from sys.version.
import sys
_ver = sys.version_info
#: Python 2.x?
is_py2 = (_ver[0] == 2)
#: Python 3.x?
is_py3 = (_ver[0] == 3)
#
# Usage
#
if is_py2:
from urllib import (
quote, unquote, quote_plus, unquote_plus, urlencode, getproxies,
proxy_bypass, proxy_bypass_environment, getproxies_environment)
from urlparse import urlparse, urlunparse, urljoin, urlsplit, urldefrag
from urllib2 import parse_http_list
import cookielib
from Cookie import Morsel
from StringIO import StringIO
from .packages.urllib3.packages.ordered_dict import OrderedDict
builtin_str = str
bytes = str
str = unicode
basestring = basestring
numeric_types = (int, long, float)
integer_types = (int, long)
elif is_py3:
from urllib.parse import urlparse, urlunparse, urljoin, urlsplit, urlencode, quote, unquote, quote_plus, unquote_plus, urldefrag
from urllib.request import parse_http_list, getproxies, proxy_bypass, proxy_bypass_environment, getproxies_environment
from http import cookiejar as cookielib
from http.cookies import Morsel
from io import StringIO
from collections import OrderedDict
builtin_str = str
str = str
bytes = bytes
basestring = (str, bytes)
numeric_types = (int, float)
integer_types = (int,)