Update requests.py

release version 2.6.1

up the version

Release 2.5.0 - Incrementing major version number

Since, package is no more a namespase package, It deems good to make it
a major release.

version 2.4.1

version 2.4

tagging v2.3

Tagging v2.2

tagging 2.0

Merge pull request #4 from jaysonsantos/master

added __getstate__ to Visitor. Thanks for jaysonsantos. see issue #3 for discussions.