升级Python2.7导致使用pip等命令安装模块失败

报错如下：

# pip
Traceback (most recent call last):
File "/usr/bin/pip", line 5, in <module>
from pkg_resources import load_entry_point
ImportError: No module named pkg_resources

其实发生这个问题是因为：虽然你已经把Python升级到了2.7版本，但是pip仍然是原来的，版本，仍然在原来python的site-package里面CentOS6.4环境下，默认是python2.6.6，site-package在/usr/lib/python2.6/site-packages/很多模块都被安装在这里。直接打pip，还是使用的原来的pip。所以我们的思路就是：应该在新的Python中安装pip，这样才不会报错。# curl -O http://python-distribute.org/distribute_setup.py # /usr/local/pyton2.7/bin/python distribute_setup.py使用新版本的python来运行这个脚本，这个会自动安装出来一个easy_install，然后使用这个新的easy_install来安装pip就可以了！# /usr/local/python/bin/easy_install pip# /usr/local/python/bin/pip -Vpip 1.4.1 from /usr/local/python/lib/python2.7/site-packages/pip-1.4.1-py2.7.egg (python 2.7)

安装生成的所有二进制文件，都是在你的PYTHON_HOME/bin/，因为我的是安装在/usr/local/python/，所以命令都在这里，以后再调用pip要使用绝对路径，或者做链接！2.7的模块是在以下目录/usr/local/python/lib/python2.7/site-packages/附：脚本的原文

#!python"""Bootstrap distribute installationIf you want to use setuptools in your package's setup.py, just include thisfile in the same directory with it, and add this to the top of your setup.py::from distribute_setup import use_setuptoolsuse_setuptools()If you want to require a specific version of setuptools, set a downloadmirror, or use an alternate download directory, you can do so by supplyingthe appropriate options to ``use_setuptools()``.This file can also be run as a script to install or upgrade setuptools."""import osimport shutilimport sysimport timeimport fnmatchimport tempfileimport tarfileimport optparsefrom distutils import logtry:from site import USER_SITEexcept ImportError:USER_SITE = Nonetry:import subprocessdef _python_cmd(*args):args = (sys.executable,) + argsreturn subprocess.call(args) == 0except ImportError:# will be used for python 2.3def _python_cmd(*args):args = (sys.executable,) + args# quoting arguments if windowsif sys.platform == 'win32':def quote(arg):if ' ' in arg:return '"%s"' % argreturn argargs = [quote(arg) for arg in args]return os.spawnl(os.P_WAIT, sys.executable, *args) == 0DEFAULT_VERSION = "0.6.49"DEFAULT_URL = "http://pypi.python.org/packages/source/d/distribute/"SETUPTOOLS_FAKED_VERSION = "0.6c11"SETUPTOOLS_PKG_INFO = """\Metadata-Version: 1.0Name: setuptoolsVersion: %sSummary: xxxxHome-page: xxxAuthor: xxxAuthor-email: xxxLicense: xxxDescription: xxx""" % SETUPTOOLS_FAKED_VERSIONdef _install(tarball, install_args=()):# extracting the tarballtmpdir = tempfile.mkdtemp()log.warn('Extracting in %s', tmpdir)old_wd = os.getcwd()try:os.chdir(tmpdir)tar = tarfile.open(tarball)_extractall(tar)tar.close()# going in the directorysubdir = os.path.join(tmpdir, os.listdir(tmpdir)[0])os.chdir(subdir)log.warn('Now working in %s', subdir)# installinglog.warn('Installing Distribute')if not _python_cmd('setup.py', 'install', *install_args):log.warn('Something went wrong during the installation.')log.warn('See the error message above.')# exitcode will be 2return 2finally:os.chdir(old_wd)shutil.rmtree(tmpdir)def _build_egg(egg, tarball, to_dir):# extracting the tarballtmpdir = tempfile.mkdtemp()log.warn('Extracting in %s', tmpdir)old_wd = os.getcwd()try:os.chdir(tmpdir)tar = tarfile.open(tarball)_extractall(tar)tar.close()# going in the directorysubdir = os.path.join(tmpdir, os.listdir(tmpdir)[0])os.chdir(subdir)log.warn('Now working in %s', subdir)# building an egglog.warn('Building a Distribute egg in %s', to_dir)_python_cmd('setup.py', '-q', 'bdist_egg', '--dist-dir', to_dir)finally:os.chdir(old_wd)shutil.rmtree(tmpdir)# returning the resultlog.warn(egg)if not os.path.exists(egg):raise IOError('Could not build the egg.')def _do_download(version, download_base, to_dir, download_delay):egg = os.path.join(to_dir, 'distribute-%s-py%d.%d.egg'% (version, sys.version_info[0], sys.version_info[1]))if not os.path.exists(egg):tarball = download_setuptools(version, download_base,to_dir, download_delay)_build_egg(egg, tarball, to_dir)sys.path.insert(0, egg)import setuptoolssetuptools.bootstrap_install_from = eggdef use_setuptools(version=DEFAULT_VERSION, download_base=DEFAULT_URL,to_dir=os.curdir, download_delay=15, no_fake=True):# making sure we use the absolute pathto_dir = os.path.abspath(to_dir)was_imported = 'pkg_resources' in sys.modules or \'setuptools' in sys.modulestry:try:import pkg_resources# Setuptools 0.7b and later is a suitable (and preferable)# substitute for any Distribute version.try:pkg_resources.require("setuptools>=0.7b")returnexcept (pkg_resources.DistributionNotFound,pkg_resources.VersionConflict):passif not hasattr(pkg_resources, '_distribute'):if not no_fake:_fake_setuptools()raise ImportErrorexcept ImportError:return _do_download(version, download_base, to_dir, download_delay)try:pkg_resources.require("distribute>=" + version)returnexcept pkg_resources.VersionConflict:e = sys.exc_info()[1]if was_imported:sys.stderr.write("The required version of distribute (>=%s) is not available,\n""and can't be installed while this script is running. Please\n""install a more recent version first, using\n""'easy_install -U distribute'.""\n\n(Currently using %r)\n" % (version, e.args[0]))sys.exit(2)else:del pkg_resources, sys.modules['pkg_resources']    # reload okreturn _do_download(version, download_base, to_dir,download_delay)except pkg_resources.DistributionNotFound:return _do_download(version, download_base, to_dir,download_delay)finally:if not no_fake:_create_fake_setuptools_pkg_info(to_dir)def download_setuptools(version=DEFAULT_VERSION, download_base=DEFAULT_URL,to_dir=os.curdir, delay=15):"""Download distribute from a specified location and return its filename`version` should be a valid distribute version number that is availableas an egg for download under the `download_base` URL (which should endwith a '/'). `to_dir` is the directory where the egg will be downloaded.`delay` is the number of seconds to pause before an actual downloadattempt."""# making sure we use the absolute pathto_dir = os.path.abspath(to_dir)try:from urllib.request import urlopenexcept ImportError:from urllib2 import urlopentgz_name = "distribute-%s.tar.gz" % versionurl = download_base + tgz_namesaveto = os.path.join(to_dir, tgz_name)src = dst = Noneif not os.path.exists(saveto):  # Avoid repeated downloadstry:log.warn("Downloading %s", url)src = urlopen(url)# Read/write all in one block, so we don't create a corrupt file# if the download is interrupted.data = src.read()dst = open(saveto, "wb")dst.write(data)finally:if src:src.close()if dst:dst.close()return os.path.realpath(saveto)def _no_sandbox(function):def __no_sandbox(*args, **kw):try:from setuptools.sandbox import DirectorySandboxif not hasattr(DirectorySandbox, '_old'):def violation(*args):passDirectorySandbox._old = DirectorySandbox._violationDirectorySandbox._violation = violationpatched = Trueelse:patched = Falseexcept ImportError:patched = Falsetry:return function(*args, **kw)finally:if patched:DirectorySandbox._violation = DirectorySandbox._olddel DirectorySandbox._oldreturn __no_sandboxdef _patch_file(path, content):"""Will backup the file then patch it"""f = open(path)existing_content = f.read()f.close()if existing_content == content:# already patchedlog.warn('Already patched.')return Falselog.warn('Patching...')_rename_path(path)f = open(path, 'w')try:f.write(content)finally:f.close()return True_patch_file = _no_sandbox(_patch_file)def _same_content(path, content):f = open(path)existing_content = f.read()f.close()return existing_content == contentdef _rename_path(path):new_name = path + '.OLD.%s' % time.time()log.warn('Renaming %s to %s', path, new_name)os.rename(path, new_name)return new_namedef _remove_flat_installation(placeholder):if not os.path.isdir(placeholder):log.warn('Unkown installation at %s', placeholder)return Falsefound = Falsefor file in os.listdir(placeholder):if fnmatch.fnmatch(file, 'setuptools*.egg-info'):found = Truebreakif not found:log.warn('Could not locate setuptools*.egg-info')returnlog.warn('Moving elements out of the way...')pkg_info = os.path.join(placeholder, file)if os.path.isdir(pkg_info):patched = _patch_egg_dir(pkg_info)else:patched = _patch_file(pkg_info, SETUPTOOLS_PKG_INFO)if not patched:log.warn('%s already patched.', pkg_info)return False# now let's move the files out of the wayfor element in ('setuptools', 'pkg_resources.py', 'site.py'):element = os.path.join(placeholder, element)if os.path.exists(element):_rename_path(element)else:log.warn('Could not find the %s element of the ''Setuptools distribution', element)return True_remove_flat_installation = _no_sandbox(_remove_flat_installation)def _after_install(dist):log.warn('After install bootstrap.')placeholder = dist.get_command_obj('install').install_purelib_create_fake_setuptools_pkg_info(placeholder)def _create_fake_setuptools_pkg_info(placeholder):if not placeholder or not os.path.exists(placeholder):log.warn('Could not find the install location')returnpyver = '%s.%s' % (sys.version_info[0], sys.version_info[1])setuptools_file = 'setuptools-%s-py%s.egg-info' % \(SETUPTOOLS_FAKED_VERSION, pyver)pkg_info = os.path.join(placeholder, setuptools_file)if os.path.exists(pkg_info):log.warn('%s already exists', pkg_info)returnlog.warn('Creating %s', pkg_info)try:f = open(pkg_info, 'w')except EnvironmentError:log.warn("Don't have permissions to write %s, skipping", pkg_info)returntry:f.write(SETUPTOOLS_PKG_INFO)finally:f.close()pth_file = os.path.join(placeholder, 'setuptools.pth')log.warn('Creating %s', pth_file)f = open(pth_file, 'w')try:f.write(os.path.join(os.curdir, setuptools_file))finally:f.close()_create_fake_setuptools_pkg_info = _no_sandbox(_create_fake_setuptools_pkg_info)def _patch_egg_dir(path):# let's check if it's already patchedpkg_info = os.path.join(path, 'EGG-INFO', 'PKG-INFO')if os.path.exists(pkg_info):if _same_content(pkg_info, SETUPTOOLS_PKG_INFO):log.warn('%s already patched.', pkg_info)return False_rename_path(path)os.mkdir(path)os.mkdir(os.path.join(path, 'EGG-INFO'))pkg_info = os.path.join(path, 'EGG-INFO', 'PKG-INFO')f = open(pkg_info, 'w')try:f.write(SETUPTOOLS_PKG_INFO)finally:f.close()return True_patch_egg_dir = _no_sandbox(_patch_egg_dir)def _before_install():log.warn('Before install bootstrap.')_fake_setuptools()def _under_prefix(location):if 'install' not in sys.argv:return Trueargs = sys.argv[sys.argv.index('install') + 1:]for index, arg in enumerate(args):for option in ('--root', '--prefix'):if arg.startswith('%s=' % option):top_dir = arg.split('root=')[-1]return location.startswith(top_dir)elif arg == option:if len(args) > index:top_dir = args[index + 1]return location.startswith(top_dir)if arg == '--user' and USER_SITE is not None:return location.startswith(USER_SITE)return Truedef _fake_setuptools():log.warn('Scanning installed packages')try:import pkg_resourcesexcept ImportError:# we're coollog.warn('Setuptools or Distribute does not seem to be installed.')returnws = pkg_resources.working_settry:setuptools_dist = ws.find(pkg_resources.Requirement.parse('setuptools', replacement=False))except TypeError:# old distribute APIsetuptools_dist = ws.find(pkg_resources.Requirement.parse('setuptools'))if setuptools_dist is None:log.warn('No setuptools distribution found')return# detecting if it was already fakedsetuptools_location = setuptools_dist.locationlog.warn('Setuptools installation detected at %s', setuptools_location)# if --root or --preix was provided, and if# setuptools is not located in them, we don't patch itif not _under_prefix(setuptools_location):log.warn('Not patching, --root or --prefix is installing Distribute'' in another location')return# let's see if its an eggif not setuptools_location.endswith('.egg'):log.warn('Non-egg installation')res = _remove_flat_installation(setuptools_location)if not res:returnelse:log.warn('Egg installation')pkg_info = os.path.join(setuptools_location, 'EGG-INFO', 'PKG-INFO')if (os.path.exists(pkg_info) and_same_content(pkg_info, SETUPTOOLS_PKG_INFO)):log.warn('Already patched.')returnlog.warn('Patching...')# let's create a fake egg replacing setuptools oneres = _patch_egg_dir(setuptools_location)if not res:returnlog.warn('Patching complete.')_relaunch()def _relaunch():log.warn('Relaunching...')# we have to relaunch the process# pip marker to avoid a relaunch bug_cmd1 = ['-c', 'install', '--single-version-externally-managed']_cmd2 = ['-c', 'install', '--record']if sys.argv[:3] == _cmd1 or sys.argv[:3] == _cmd2:sys.argv[0] = 'setup.py'args = [sys.executable] + sys.argvsys.exit(subprocess.call(args))def _extractall(self, path=".", members=None):"""Extract all members from the archive to the current workingdirectory and set owner, modification time and permissions ondirectories afterwards. `path' specifies a different directoryto extract to. `members' is optional and must be a subset of thelist returned by getmembers()."""import copyimport operatorfrom tarfile import ExtractErrordirectories = []if members is None:members = selffor tarinfo in members:if tarinfo.isdir():# Extract directories with a safe mode.directories.append(tarinfo)tarinfo = copy.copy(tarinfo)tarinfo.mode = 448  # decimal for oct 0700self.extract(tarinfo, path)# Reverse sort directories.if sys.version_info < (2, 4):def sorter(dir1, dir2):return cmp(dir1.name, dir2.name)directories.sort(sorter)directories.reverse()else:directories.sort(key=operator.attrgetter('name'), reverse=True)# Set correct owner, mtime and filemode on directories.for tarinfo in directories:dirpath = os.path.join(path, tarinfo.name)try:self.chown(tarinfo, dirpath)self.utime(tarinfo, dirpath)self.chmod(tarinfo, dirpath)except ExtractError:e = sys.exc_info()[1]if self.errorlevel > 1:raiseelse:self._dbg(1, "tarfile: %s" % e)def _build_install_args(options):"""Build the arguments to 'python setup.py install' on the distribute package"""install_args = []if options.user_install:if sys.version_info < (2, 6):log.warn("--user requires Python 2.6 or later")raise SystemExit(1)install_args.append('--user')return install_argsdef _parse_args():"""Parse the command line for options"""parser = optparse.OptionParser()parser.add_option('--user', dest='user_install', action='store_true', default=False,help='install in user site package (requires Python 2.6 or later)')parser.add_option('--download-base', dest='download_base', metavar="URL",default=DEFAULT_URL,help='alternative URL from where to download the distribute package')options, args = parser.parse_args()# positional arguments are ignoredreturn optionsdef main(version=DEFAULT_VERSION):"""Install or upgrade setuptools and EasyInstall"""options = _parse_args()tarball = download_setuptools(download_base=options.download_base)return _install(tarball, _build_install_args(options))if __name__ == '__main__':sys.exit(main())