导入错误：没有名为烧瓶的模块 - uwsgi 和 buildout

Question

uWSGI 配置：

<uwsgi>
    <module>app_wsgi:app</module>
    <pythonpath>./src</pythonpath>
    <socket>/tmp/uwsgi.sock</socket>
    <pidfile>/tmp/uwsgi.pid</pidfile>
    <daemonize>uwsgi.log</daemonize>
</uwsgi>

配置文件

[buildout]
parts = eggs uwsgi
versions = versions
include-site-packages = false

[eggs]
recipe: zc.recipe.egg:eggs
eggs =
    flask

[versions]
flask = 0.9

[uwsgi]
recipe: buildout.recipe.uwsgi
version = 1.4.3

例外：

*** Operational MODE: single process ***
added ./src/ to pythonpath.
Traceback (most recent call last):
  File "./src/app_wsgi.py", line 1, in <module>
    from app import create_app
  File "./src/app.py", line 1, in <module>
    from flask import Flask, request
ImportError: No module named flask
unable to load app 0 (mountpoint='') (callable not found or import error)

在virtualenv 的情况下如何解决这个问题很清楚，但是有了 buildout 一切都变得更加复杂。手动更改 pythonpath 不是解决方案。有任何想法吗？