python – 没有名为dateutil.parser的模块

我收到一个错误：

Traceback (most recent call last):
  File "manage.py",line 9,in <module>
    execute_from_command_line(sys.argv)
  File "/home/osboxes/dev/projects/rapidpro/rapidpro/env/local/lib/python2.7/site-packages/django/core/management/__init__.py",line 385,in execute_from_command_line
    utility.execute()
  File "/home/osboxes/dev/projects/rapidpro/rapidpro/env/local/lib/python2.7/site-packages/django/core/management/__init__.py",line 354,in execute
    django.setup()
  File "/home/osboxes/dev/projects/rapidpro/rapidpro/env/local/lib/python2.7/site-packages/django/__init__.py",line 21,in setup
    apps.populate(settings.INSTALLED_APPS)
  File "/home/osboxes/dev/projects/rapidpro/rapidpro/env/local/lib/python2.7/site-packages/django/apps/registry.py",line 85,in populate
    app_config = AppConfig.create(entry)
  File "/home/osboxes/dev/projects/rapidpro/rapidpro/env/local/lib/python2.7/site-packages/django/apps/config.py",line 123,in create
    import_module(entry)
  File "/usr/lib/python2.7/importlib/__init__.py",line 37,in import_module
    __import__(name)
  File "/home/osboxes/dev/projects/rapidpro/rapidpro/temba/utils/__init__.py",in <module>
    from dateutil.parser import parse
ImportError: No module named dateutil.parser

我按照这篇文章中的步骤：ImportError: No module named dateutil.parser,但无济于事！ (攻击和使用点子)

我是一个完整的Python菜鸟,所以我很有可能忽略了一些明显的东西.我在Ubuntu 15.04上安装.

想法？谢谢！