虚拟环境上的Pip安装在依赖包的版本上引发错误

Question

我们正在尝试安装OpenStack服务。我们已经创建了虚拟环境并安装了Pip。Pip版本是8.1.1。现在，当我们尝试安装keystone时，我们会得到依赖包的错误，如下所示：

/tmp/openstack-venv-builder/venvs/horizon/bin/pip install --timeout 120 --find-links /var/www/repo/os-releases/liberty --no-index --log /var/log/repo/repo_venv_builder.log keystone
Ignoring indexes: http://pypi.python.org/simple
Collecting keystone
Collecting oslo.i18n<1.6.0,>=1.5.0 (from keystone)

  Could not find a version that satisfies the requirement oslo.i18n<1.6.0,>=1.5.0 (from keystone) (from versions: 3.1.0)
No matching distribution found for oslo.i18n<1.6.0,>=1.5.0 (from keystone)

安装在oslo.i18n上看起来不错。在

^{pr2}$