使用 pip 重新安装需求文件

我尝试使用 pip 重新安装项目的要求，但收到此错误。之前有一个失败的安装。我怎样才能删除它并继续？

E:\projects\project course\tkz>pip install -r requirements.txt
Downloading/unpacking Django==1.5.4 (from -r requirements.txt (line 1))
pip can't proceed with requirement 'Django==1.5.4 (from -r requirements.txt (lin
e 1))' due to a pre-existing build directory.
location: c:\users\sina\appdata\local\temp\pip_build_sina\Django
This is likely due to a previous installation that failed.
pip is being responsible and not assuming it can delete this.
Please delete it and try again.

Cleaning up...

Use:

pip uninstall Django==1.5.4

or

pip uninstall -r requirements.txt

如果还是不行，那就进入你的内心吧Python/Lib/site-packages这些包所在的目录，然后删除它们。然后重新运行

pip install -r requirements.txt

那应该有效。