安装python的easy_install和pip

一  安装介绍：

安装地址： https://pypi.python.org/pypi/setuptools#id9

Installation Instructions

The recommended way to bootstrap setuptools on any system is to download ez_setup.py and run it using the target Python environment. Different operating systems have different recommended techniques to accomplish this basic routine, so below are some examples to get you started.

Setuptools requires Python 2.6 or later. To install setuptools on Python 2.4 or Python 2.5, use thebootstrap script for Setuptools 1.x.

The link provided to ez_setup.py is a bookmark to bootstrap script for the latest known stable release.

window安装：

Windows (Powershell 3 or later)

For best results, uninstall previous versions FIRST (see Uninstalling).

Using Windows 8 (which includes PowerShell 3) or earlier versions of Windows with PowerShell 3 installed, it’s possible to install with one simple Powershell command. Start up Powershell and paste this command:

> (Invoke-WebRequest https://bootstrap.pypa.io/ez_setup.py).Content | python -

You must start the Powershell with Administrative privileges or you may choose to install a user-local installation:

> (Invoke-WebRequest https://bootstrap.pypa.io/ez_setup.py).Content | python - --user

If you have Python 3.3 or later, you can use the py command to install to different Python versions. For example, to install to Python 3.3 if you have Python 2.7 installed:

> (Invoke-WebRequest https://bootstrap.pypa.io/ez_setup.py).Content | py -3 -

The recommended way to install setuptools on Windows is to download ez_setup.py and run it. The script will download the appropriate distribution file and install it for you.

Once installation is complete, you will find an easy_install program in your Python Scriptssubdirectory. For simple invocation and best results, add this directory to your PATH environment variable, if it is not already present. If you did a user-local install, the Scripts subdirectory is$env:APPDATA\Python\Scripts.

Windows (simplified)

For Windows without PowerShell 3 or for installation without a command-line, download ez_setup.pyusing your preferred web browser or other technique and “run” that file.

linux安装：

Unix (wget)

Most Linux distributions come with wget.

Download ez_setup.py and run it using the target Python version. The script will download the appropriate version and install it for you:

> wget https://bootstrap.pypa.io/ez_setup.py -O - | python

Note that you will may need to invoke the command with superuser privileges to install to the system Python:

> wget https://bootstrap.pypa.io/ez_setup.py -O - | sudo python

Alternatively, Setuptools may be installed to a user-local path:

> wget https://bootstrap.pypa.io/ez_setup.py -O - | python - --user

Note that on some older systems (noted on Debian 6 and CentOS 5 installations),wgetmay refuse to downloadez_setup.py, complaining that the certificate common name*.c.ssl.fastly.netdoes not match the host namebootstrap.pypa.io. In addition, theez_setup.pyscript may then encounter similar problems usingwgetinternally to downloadsetuptools-x.y.zip, complaining that the certificate common name ofwww.python.orgdoes not match the host namepypi.python.org. Those are known issues, related to a bug in the older versions ofwget(see Issue 59). If you happen to encounter them, install Setuptools as follows:

> wget --no-check-certificate https://bootstrap.pypa.io/ez_setup.py
> python ez_setup.py --insecure

mac安装:

Unix including Mac OS X (curl)

If your system has curl installed, follow the wget instructions but replace wget with curl and -O with-o. For example:

> curl https://bootstrap.pypa.io/ez_setup.py -o - | python

自定义安装：

Advanced Installation

For more advanced installation options, such as installing to custom locations or prefixes, download and extract the source tarball from Setuptools on PyPIand run setup.py with any supported distutils and Setuptools options. For example:

setuptools-x.x$ python setup.py install --prefix=/opt/setuptools

Use --help to get a full options list, but we recommend consulting the EasyInstall manual for detailed instructions, especially the section on custom installation locations.

二  演示：

主机版本：

[root@master progressbar-2.3]# cat /etc/centos-release 
CentOS release 6.7 (Final)

安装：

[root@master progressbar-2.3]#  wget https://bootstrap.pypa.io/ez_setup.py -O - | python
--2016-01-11 07:15:01--  https://bootstrap.pypa.io/ez_setup.py  
Resolving bootstrap.pypa.io... 185.31.18.175  
Connecting to bootstrap.pypa.io|185.31.18.175|:443... connected.  
HTTP request sent, awaiting response... 200 OK  
Length: 12059 (12K) [text/x-python]  
Saving to: “STDOUT”

100%[===========================================>] 12,059      --.-K/s   in 0s     

2016-01-11 07:15:09 (432 MB/s) - written to stdout [12059/12059]

Downloading https://pypi.python.org/packages/source/s/setuptools/setuptools-19.2.zip  
Extracting in /tmp/tmpQGjSJl  
Now working in /tmp/tmpQGjSJl/setuptools-19.2  
Installing Setuptools  
running install  
running bdist_egg  
running egg_info  
writing requirements to setuptools.egg-info/requires.txt  
writing setuptools.egg-info/PKG-INFO  
writing top-level names to setuptools.egg-info/top_level.txt  
writing dependency_links to setuptools.egg-info/dependency_links.txt  
writing entry points to setuptools.egg-info/entry_points.txt  
reading manifest file 'setuptools.egg-info/SOURCES.txt'  
reading manifest template 'MANIFEST.in'  
writing manifest file 'setuptools.egg-info/SOURCES.txt'  
installing library code to build/bdist.linux-i686/egg  
running install_lib  
running build_py  
creating build  
creating build/lib  
copying easy_install.py -> build/lib  
creating build/lib/setuptools  
copying setuptools/site-patch.py -> build/lib/setuptools  
copying setuptools/utils.py -> build/lib/setuptools  
copying setuptools/__init__.py -> build/lib/setuptools  
copying setuptools/package_index.py -> build/lib/setuptools  
copying setuptools/ssl_support.py -> build/lib/setuptools  
copying setuptools/version.py -> build/lib/setuptools  
copying setuptools/msvc9_support.py -> build/lib/setuptools  
copying setuptools/py27compat.py -> build/lib/setuptools  
copying setuptools/compat.py -> build/lib/setuptools  
copying setuptools/extension.py -> build/lib/setuptools  
copying setuptools/windows_support.py -> build/lib/setuptools  
copying setuptools/unicode_utils.py -> build/lib/setuptools  
copying setuptools/py31compat.py -> build/lib/setuptools  
copying setuptools/py26compat.py -> build/lib/setuptools  
copying setuptools/archive_util.py -> build/lib/setuptools  
copying setuptools/dist.py -> build/lib/setuptools  
copying setuptools/sandbox.py -> build/lib/setuptools  
copying setuptools/lib2to3_ex.py -> build/lib/setuptools  
copying setuptools/depends.py -> build/lib/setuptools  
creating build/lib/_markerlib  
copying _markerlib/__init__.py -> build/lib/_markerlib  
copying _markerlib/markers.py -> build/lib/_markerlib  
creating build/lib/pkg_resources  
copying pkg_resources/__init__.py -> build/lib/pkg_resources  
creating build/lib/setuptools/command  
copying setuptools/command/rotate.py -> build/lib/setuptools/command  
copying setuptools/command/easy_install.py -> build/lib/setuptools/command  
copying setuptools/command/__init__.py -> build/lib/setuptools/command  
copying setuptools/command/setopt.py -> build/lib/setuptools/command  
copying setuptools/command/build_py.py -> build/lib/setuptools/command  
copying setuptools/command/build_ext.py -> build/lib/setuptools/command  
copying setuptools/command/install_egg_info.py -> build/lib/setuptools/command  
copying setuptools/command/install_scripts.py -> build/lib/setuptools/command  
copying setuptools/command/sdist.py -> build/lib/setuptools/command  
copying setuptools/command/bdist_wininst.py -> build/lib/setuptools/command  
copying setuptools/command/bdist_rpm.py -> build/lib/setuptools/command  
copying setuptools/command/test.py -> build/lib/setuptools/command  
copying setuptools/command/install.py -> build/lib/setuptools/command  
copying setuptools/command/saveopts.py -> build/lib/setuptools/command  
copying setuptools/command/egg_info.py -> build/lib/setuptools/command  
copying setuptools/command/register.py -> build/lib/setuptools/command  
copying setuptools/command/bdist_egg.py -> build/lib/setuptools/command  
copying setuptools/command/develop.py -> build/lib/setuptools/command  
copying setuptools/command/install_lib.py -> build/lib/setuptools/command  
copying setuptools/command/alias.py -> build/lib/setuptools/command  
copying setuptools/command/upload_docs.py -> build/lib/setuptools/command  
creating build/lib/pkg_resources/_vendor  
copying pkg_resources/_vendor/__init__.py -> build/lib/pkg_resources/_vendor  
creating build/lib/pkg_resources/_vendor/packaging  
copying pkg_resources/_vendor/packaging/specifiers.py -> build/lib/pkg_resources/_vendor/packaging  
copying pkg_resources/_vendor/packaging/__init__.py -> build/lib/pkg_resources/_vendor/packaging  
copying pkg_resources/_vendor/packaging/version.py -> build/lib/pkg_resources/_vendor/packaging  
copying pkg_resources/_vendor/packaging/_compat.py -> build/lib/pkg_resources/_vendor/packaging  
copying pkg_resources/_vendor/packaging/_structures.py -> build/lib/pkg_resources/_vendor/packaging  
copying pkg_resources/_vendor/packaging/__about__.py -> build/lib/pkg_resources/_vendor/packaging  
copying setuptools/script (dev).tmpl -> build/lib/setuptools  
copying setuptools/script.tmpl -> build/lib/setuptools  
creating build/bdist.linux-i686  
creating build/bdist.linux-i686/egg  
copying build/lib/easy_install.py -> build/bdist.linux-i686/egg  
creating build/bdist.linux-i686/egg/setuptools  
copying build/lib/setuptools/site-patch.py -> build/bdist.linux-i686/egg/setuptools  
copying build/lib/setuptools/utils.py -> build/bdist.linux-i686/egg/setuptools  
copying build/lib/setuptools/__init__.py -> build/bdist.linux-i686/egg/setuptools  
copying build/lib/setuptools/script (dev).tmpl -> build/bdist.linux-i686/egg/setuptools  
copying build/lib/setuptools/package_index.py -> build/bdist.linux-i686/egg/setuptools  
copying build/lib/setuptools/ssl_support.py -> build/bdist.linux-i686/egg/setuptools  
copying build/lib/setuptools/version.py -> build/bdist.linux-i686/egg/setuptools  
copying build/lib/setuptools/msvc9_support.py -> build/bdist.linux-i686/egg/setuptools  
copying build/lib/setuptools/py27compat.py -> build/bdist.linux-i686/egg/setuptools  
copying build/lib/setuptools/compat.py -> build/bdist.linux-i686/egg/setuptools  
copying build/lib/setuptools/extension.py -> build/bdist.linux-i686/egg/setuptools  
copying build/lib/setuptools/windows_support.py -> build/bdist.linux-i686/egg/setuptools  
copying build/lib/setuptools/unicode_utils.py -> build/bdist.linux-i686/egg/setuptools  
creating build/bdist.linux-i686/egg/setuptools/command  
copying build/lib/setuptools/command/rotate.py -> build/bdist.linux-i686/egg/setuptools/command  
copying build/lib/setuptools/command/easy_install.py -> build/bdist.linux-i686/egg/setuptools/command  
copying build/lib/setuptools/command/__init__.py -> build/bdist.linux-i686/egg/setuptools/command  
copying build/lib/setuptools/command/setopt.py -> build/bdist.linux-i686/egg/setuptools/command  
copying build/lib/setuptools/command/build_py.py -> build/bdist.linux-i686/egg/setuptools/command  
copying build/lib/setuptools/command/build_ext.py -> build/bdist.linux-i686/egg/setuptools/command  
copying build/lib/setuptools/command/install_egg_info.py -> build/bdist.linux-i686/egg/setuptools/command  
copying build/lib/setuptools/command/install_scripts.py -> build/bdist.linux-i686/egg/setuptools/command  
copying build/lib/setuptools/command/sdist.py -> build/bdist.linux-i686/egg/setuptools/command  
copying build/lib/setuptools/command/bdist_wininst.py -> build/bdist.linux-i686/egg/setuptools/command  
copying build/lib/setuptools/command/bdist_rpm.py -> build/bdist.linux-i686/egg/setuptools/command  
copying build/lib/setuptools/command/test.py -> build/bdist.linux-i686/egg/setuptools/command  
copying build/lib/setuptools/command/install.py -> build/bdist.linux-i686/egg/setuptools/command  
copying build/lib/setuptools/command/saveopts.py -> build/bdist.linux-i686/egg/setuptools/command  
copying build/lib/setuptools/command/egg_info.py -> build/bdist.linux-i686/egg/setuptools/command  
copying build/lib/setuptools/command/register.py -> build/bdist.linux-i686/egg/setuptools/command  
copying build/lib/setuptools/command/bdist_egg.py -> build/bdist.linux-i686/egg/setuptools/command  
copying build/lib/setuptools/command/develop.py -> build/bdist.linux-i686/egg/setuptools/command  
copying build/lib/setuptools/command/install_lib.py -> build/bdist.linux-i686/egg/setuptools/command  
copying build/lib/setuptools/command/alias.py -> build/bdist.linux-i686/egg/setuptools/command  
copying build/lib/setuptools/command/upload_docs.py -> build/bdist.linux-i686/egg/setuptools/command  
copying build/lib/setuptools/script.tmpl -> build/bdist.linux-i686/egg/setuptools  
copying build/lib/setuptools/py31compat.py -> build/bdist.linux-i686/egg/setuptools  
copying build/lib/setuptools/py26compat.py -> build/bdist.linux-i686/egg/setuptools  
copying build/lib/setuptools/archive_util.py -> build/bdist.linux-i686/egg/setuptools  
copying build/lib/setuptools/dist.py -> build/bdist.linux-i686/egg/setuptools  
copying build/lib/setuptools/sandbox.py -> build/bdist.linux-i686/egg/setuptools  
copying build/lib/setuptools/lib2to3_ex.py -> build/bdist.linux-i686/egg/setuptools  
copying build/lib/setuptools/depends.py -> build/bdist.linux-i686/egg/setuptools  
creating build/bdist.linux-i686/egg/_markerlib  
copying build/lib/_markerlib/__init__.py -> build/bdist.linux-i686/egg/_markerlib  
copying build/lib/_markerlib/markers.py -> build/bdist.linux-i686/egg/_markerlib  
creating build/bdist.linux-i686/egg/pkg_resources  
copying build/lib/pkg_resources/__init__.py -> build/bdist.linux-i686/egg/pkg_resources  
creating build/bdist.linux-i686/egg/pkg_resources/_vendor  
copying build/lib/pkg_resources/_vendor/__init__.py -> build/bdist.linux-i686/egg/pkg_resources/_vendor  
creating build/bdist.linux-i686/egg/pkg_resources/_vendor/packaging  
copying build/lib/pkg_resources/_vendor/packaging/specifiers.py -> build/bdist.linux-i686/egg/pkg_resources/_vendor/packaging  
copying build/lib/pkg_resources/_vendor/packaging/__init__.py -> build/bdist.linux-i686/egg/pkg_resources/_vendor/packaging  
copying build/lib/pkg_resources/_vendor/packaging/version.py -> build/bdist.linux-i686/egg/pkg_resources/_vendor/packaging  
copying build/lib/pkg_resources/_vendor/packaging/_compat.py -> build/bdist.linux-i686/egg/pkg_resources/_vendor/packaging  
copying build/lib/pkg_resources/_vendor/packaging/_structures.py -> build/bdist.linux-i686/egg/pkg_resources/_vendor/packaging  
copying build/lib/pkg_resources/_vendor/packaging/__about__.py -> build/bdist.linux-i686/egg/pkg_resources/_vendor/packaging  
byte-compiling build/bdist.linux-i686/egg/easy_install.py to easy_install.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/site-patch.py to site-patch.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/utils.py to utils.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/__init__.py to __init__.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/package_index.py to package_index.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/ssl_support.py to ssl_support.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/version.py to version.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/msvc9_support.py to msvc9_support.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/py27compat.py to py27compat.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/compat.py to compat.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/extension.py to extension.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/windows_support.py to windows_support.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/unicode_utils.py to unicode_utils.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/command/rotate.py to rotate.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/command/easy_install.py to easy_install.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/command/__init__.py to __init__.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/command/setopt.py to setopt.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/command/build_py.py to build_py.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/command/build_ext.py to build_ext.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/command/install_egg_info.py to install_egg_info.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/command/install_scripts.py to install_scripts.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/command/sdist.py to sdist.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/command/bdist_wininst.py to bdist_wininst.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/command/bdist_rpm.py to bdist_rpm.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/command/test.py to test.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/command/install.py to install.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/command/saveopts.py to saveopts.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/command/egg_info.py to egg_info.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/command/register.py to register.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/command/bdist_egg.py to bdist_egg.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/command/develop.py to develop.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/command/install_lib.py to install_lib.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/command/alias.py to alias.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/command/upload_docs.py to upload_docs.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/py31compat.py to py31compat.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/py26compat.py to py26compat.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/archive_util.py to archive_util.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/dist.py to dist.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/sandbox.py to sandbox.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/lib2to3_ex.py to lib2to3_ex.pyc  
byte-compiling build/bdist.linux-i686/egg/setuptools/depends.py to depends.pyc  
byte-compiling build/bdist.linux-i686/egg/_markerlib/__init__.py to __init__.pyc  
byte-compiling build/bdist.linux-i686/egg/_markerlib/markers.py to markers.pyc  
byte-compiling build/bdist.linux-i686/egg/pkg_resources/__init__.py to __init__.pyc  
byte-compiling build/bdist.linux-i686/egg/pkg_resources/_vendor/__init__.py to __init__.pyc  
byte-compiling build/bdist.linux-i686/egg/pkg_resources/_vendor/packaging/specifiers.py to specifiers.pyc  
byte-compiling build/bdist.linux-i686/egg/pkg_resources/_vendor/packaging/__init__.py to __init__.pyc  
byte-compiling build/bdist.linux-i686/egg/pkg_resources/_vendor/packaging/version.py to version.pyc  
byte-compiling build/bdist.linux-i686/egg/pkg_resources/_vendor/packaging/_compat.py to _compat.pyc  
byte-compiling build/bdist.linux-i686/egg/pkg_resources/_vendor/packaging/_structures.py to _structures.pyc  
byte-compiling build/bdist.linux-i686/egg/pkg_resources/_vendor/packaging/__about__.py to __about__.pyc  
creating build/bdist.linux-i686/egg/EGG-INFO  
copying setuptools.egg-info/PKG-INFO -> build/bdist.linux-i686/egg/EGG-INFO  
copying setuptools.egg-info/SOURCES.txt -> build/bdist.linux-i686/egg/EGG-INFO  
copying setuptools.egg-info/dependency_links.txt -> build/bdist.linux-i686/egg/EGG-INFO  
copying setuptools.egg-info/entry_points.txt -> build/bdist.linux-i686/egg/EGG-INFO  
copying setuptools.egg-info/requires.txt -> build/bdist.linux-i686/egg/EGG-INFO  
copying setuptools.egg-info/top_level.txt -> build/bdist.linux-i686/egg/EGG-INFO  
copying setuptools.egg-info/zip-safe -> build/bdist.linux-i686/egg/EGG-INFO  
creating dist  
creating 'dist/setuptools-19.2-py2.6.egg' and adding 'build/bdist.linux-i686/egg' to it  
removing 'build/bdist.linux-i686/egg' (and everything under it)  
Processing setuptools-19.2-py2.6.egg  
Copying setuptools-19.2-py2.6.egg to /usr/lib/python2.6/site-packages  
Adding setuptools 19.2 to easy-install.pth file  
Installing easy_install script to /usr/bin  
Installing easy_install-2.6 script to /usr/bin

Installed /usr/lib/python2.6/site-packages/setuptools-19.2-py2.6.egg  
Processing dependencies for setuptools==19.2  
Finished processing dependencies for setuptools==19.2

验证：

[root@master progressbar-2.3]# easy_install pip  
Searching for pip  
Reading https://pypi.python.org/simple/pip/  
Best match: pip 7.1.2  
Downloading https://pypi.python.org/packages/source/p/pip/pip-7.1.2.tar.gz#md5=3823d2343d9f3aaab21cf9c917710196  
Processing pip-7.1.2.tar.gz  
Writing /tmp/easy_install-dAri8v/pip-7.1.2/setup.cfg  
Running pip-7.1.2/setup.py -q bdist_egg --dist-dir /tmp/easy_install-dAri8v/pip-7.1.2/egg-dist-tmp-PwaE1u  
warning: no previously-included files found matching '.coveragerc'  
warning: no previously-included files found matching '.mailmap'  
warning: no previously-included files found matching '.travis.yml'  
warning: no previously-included files found matching 'pip/_vendor/Makefile'  
warning: no previously-included files found matching 'tox.ini'  
warning: no previously-included files found matching 'dev-requirements.txt'  
no previously-included directories found matching '.travis'  
no previously-included directories found matching 'docs/_build'  
no previously-included directories found matching 'contrib'  
no previously-included directories found matching 'tasks'  
no previously-included directories found matching 'tests'  
creating /usr/lib/python2.6/site-packages/pip-7.1.2-py2.6.egg  
Extracting pip-7.1.2-py2.6.egg to /usr/lib/python2.6/site-packages  
Adding pip 7.1.2 to easy-install.pth file  
Installing pip script to /usr/bin  
Installing pip2.6 script to /usr/bin  
Installing pip2 script to /usr/bin

Installed /usr/lib/python2.6/site-packages/pip-7.1.2-py2.6.egg  
Processing dependencies for pip  
Finished processing dependencies for pip  
[root@master progressbar-2.3]# echo $?  
0

三  使用说明：

easy_install 安�b�c移除套件的基本使用方式如下：

安�b套件：

easy_install PackageName

更新套件：

easy_install -U PackageName

移除套件：

easy_install -m PackageName

�@示�f明：

easy_install --showhelp

pip  安�b�c移除套件的基本使用方式如下：

安�b套件：

pip install PackageName

更新套件：

pip install -U PackageName

移除套件：

pip uninstall PackageName

搜�ぬ准�：

pip search PackageName

�@示�f明：

pip help