pyvenv, setuptools, pip

myenv.py

#!/usr/bin/python3
import argparse
import os
import subprocess
import sys
import tempfile
import urllib.request
import venv

setuptools_version = "1.1.6"
EZ_SETUP_URL = 'https://bitbucket.org/pypa/setuptools/raw/{version}/ez_setup.py'.format(version=setuptools_version)
GET_PIP_URL = 'https://raw.github.com/pypa/pip/develop/contrib/get-pip.py'


def exec_env(context, script_file):
    print("execute {0}".format(script_file))
    subprocess.check_call([context.env_exe, script_file])


class MyEnvBuilder(venv.EnvBuilder):

    def post_setup(self, context):
        self.install_pypa(context)

    def install_pypa(self, context):
        with tempfile.TemporaryDirectory() as d:
            self.install_setuptools(context, d)
            self.install_pip(context, d)

    def install_setuptools(self, context, d):
        path = self.download(EZ_SETUP_URL, d)
        exec_env(context, path)

    def install_pip(self, context, d):
        path = self.download(GET_PIP_URL, d)
        exec_env(context, path)

    def download(self, url, d):
        print("downloading {url}".format(url=url))
        filename = url.split("/")[-1]
        path = os.path.join(d, filename)
        with urllib.request.urlopen(url) as f:
            with open(path, "wb") as out:
                out.write(f.read())
        print("done")
        return path


def main(args=sys.argv[1:]):
    parser = argparse.ArgumentParser()
    parser.add_argument("envdir")
    args = parser.parse_args(args)
    builder = MyEnvBuilder()
    builder.create(args.envdir)


if __name__ == '__main__':
    main()