"""By using execfile(this_file, dict(__file__=this_file)) you will

activate this virtualenv environment.

This can be used when you must use an existing Python interpreter, not

the virtualenv bin/python

"""

try:

    __file__

except NameError:

    raise AssertionError(

        "You must run this like execfile('path/to/active_this.py', dict(__file__='path/to/activate_this.py'))")

import sys

import os

base = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))

site_packages = os.path.join(base, 'lib', 'python%s' % sys.version[:3], 'site-packages')

prev_sys_path = list(sys.path)

import site

site.addsitedir(site_packages)

sys.real_prefix = sys.prefix

sys.prefix = base

# Move the added items to the front of the path:

new_sys_path = []

for item in list(sys.path):

    if item not in prev_sys_path:

        new_sys_path.append(item)

        sys.path.remove(item)

sys.path[:0] = new_sys_path