我正在尝试设置虚拟环境，但出现以下错误：
$virtualenv ./olp/
New python executable in ./olp/bin/python
Installing setuptools............done.
Installing pip.....
Complete output from command /home/tom/Documents/Dev/olp/bin/python -x /home/tom/Documents/Dev/olp/bin/easy_install ./pip-X.X.tar.gz:
Processing pip-X.X.tar.gz
error: Not a recognized archive type: ./pip-X.X.tar.gz
----------------------------------------
...Installing pip...done.
Traceback (most recent call last):
File "/usr/local/bin/virtualenv", line 9, in <module>
load_entry_point('virtualenv==1.9.1', 'console_scripts', 'virtualenv')()
File "/usr/local/lib/python2.7/dist-packages/virtualenv.py", line 979, in main
no_pip=options.no_pip)
File "/usr/local/lib/python2.7/dist-packages/virtualenv.py", line 1094, in create_environment
install_pip(py_executable, search_dirs=search_dirs, never_download=never_download)
File "/usr/local/lib/python2.7/dist-packages/virtualenv.py", line 667, in install_pip
filter_stdout=_filter_setup)
File "/usr/local/lib/python2.7/dist-packages/virtualenv.py", line 1057, in call_subprocess
% (cmd_desc, proc.returncode))
OSError: Command /home/tom/Documents/Dev/olp/bin/python -x /home/tom/Documents/Dev/olp/bin/easy_install ./pip-X.X.tar.gz failed with error code 1
然后似乎创建了虚拟环境：
olp$ tree
.
├── bin
│ ├── easy_install
│ ├── easy_install-2.7
│ ├── python
│ ├── python2 -> python
│ └── python2.7 -> python
├── include
│ └── python2.7 -> /usr/include/python2.7
├── lib
│ └── python2.7
│ ├── _abcoll.py -> /usr/lib/python2.7/_abcoll.py
│ ├── _abcoll.pyc
│ ├── abc.py -> /usr/lib/python2.7/abc.py
│ ├── abc.pyc
│ ├── codecs.py -> /usr/lib/python2.7/codecs.py
│ ├── codecs.pyc
│ ├── config -> /usr/lib/python2.7/config
│ ├── copy_reg.py -> /usr/lib/python2.7/copy_reg.py
│ ├── copy_reg.pyc
│ ├── distutils
│ │ ├── distutils.cfg
│ │ ├── __init__.py
│ │ └── __init__.pyc
│ ├── encodings -> /usr/lib/python2.7/encodings
│ ├── fnmatch.py -> /usr/lib/python2.7/fnmatch.py
│ ├── fnmatch.pyc
│ ├── genericpath.py -> /usr/lib/python2.7/genericpath.py
│ ├── genericpath.pyc
│ ├── lib-dynload -> /usr/lib/python2.7/lib-dynload
│ ├── linecache.py -> /usr/lib/python2.7/linecache.py
│ ├── linecache.pyc
│ ├── locale.py -> /usr/lib/python2.7/locale.py
│ ├── no-global-site-packages.txt
│ ├── ntpath.py -> /usr/lib/python2.7/ntpath.py
│ ├── orig-prefix.txt
│ ├── os.py -> /usr/lib/python2.7/os.py
│ ├── os.pyc
│ ├── posixpath.py -> /usr/lib/python2.7/posixpath.py
│ ├── posixpath.pyc
│ ├── re.py -> /usr/lib/python2.7/re.py
│ ├── re.pyc
│ ├── site-packages
│ │ ├── easy-install.pth
│ │ ├── setuptools-0.6c11-py2.7.egg
│ │ └── setuptools.pth
│ ├── site.py
│ ├── site.pyc
│ ├── sre_compile.py -> /usr/lib/python2.7/sre_compile.py
│ ├── sre_compile.pyc
│ ├── sre_constants.py -> /usr/lib/python2.7/sre_constants.py
│ ├── sre_constants.pyc
│ ├── sre_parse.py -> /usr/lib/python2.7/sre_parse.py
│ ├── sre_parse.pyc
│ ├── sre.py -> /usr/lib/python2.7/sre.py
│ ├── stat.py -> /usr/lib/python2.7/stat.py
│ ├── stat.pyc
│ ├── types.py -> /usr/lib/python2.7/types.py
│ ├── types.pyc
│ ├── UserDict.py -> /usr/lib/python2.7/UserDict.py
│ ├── UserDict.pyc
│ ├── warnings.py -> /usr/lib/python2.7/warnings.py
│ ├── warnings.pyc
│ ├── _weakrefset.py -> /usr/lib/python2.7/_weakrefset.py
│ └── _weakrefset.pyc
└── local
├── bin -> /home/tom/Documents/Dev/olp/bin
├── include -> /home/tom/Documents/Dev/olp/include
└── lib -> /home/tom/Documents/Dev/olp/lib
谁能帮我解决错误？我做错什么了？