我从自制软件安装python（os x mavericks）并从{pip {1}}安装了jrnl，但是当我运行上述实用程序时，我提示错误：
sudo pip install jrnl我正在运行Python 2.7.5，而我的> Traceback (most recent call last): File "/usr/local/bin/jrnl", line
> 5, in <module>
> from pkg_resources import load_entry_point File "/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/pkg_resources.py",
> line 2603, in <module>
> working_set.require(__requires__) File "/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/pkg_resources.py",
> line 666, in require
> needed = self.resolve(parse_requirements(requirements)) File "/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/pkg_resources.py",
> line 565, in resolve
> raise DistributionNotFound(req) # XXX put more info here
> pkg_resources.DistributionNotFound: python-dateutil>=2.2
和which python命令会将which pip和/usr/bin/python作为结果resp。我的安装有什么问题？