我正在尝试构建OpenERP项目，并完成了依赖项。现在出现此错误

Traceback (most recent call last):
  File "openerp-client.py", line 105, in <module>
  File "modules\__init__.pyo", line 23, in <module>
  File "modules\gui\__init__.pyo", line 22, in <module>
  File "modules\gui\main.pyo", line 33, in <module>
  File "rpc.pyo", line 29, in <module>
  File "common\__init__.pyo", line 22, in <module>
  File "common\common.pyo", line 26, in <module>
  File "tools\__init__.pyo", line 28, in <module>
  File "dateutil\relativedelta.pyo", line 12, in <module>
ImportError: No module named six

有人可以指导出什么问题以及如何解决吗？？？