我正在尝试在windows上使用easy_install安装“pwd”模块，遇到以下错误，有人可以帮助修复此错误吗？C:\Dropbox\scripts>easy_install pwd

Searching for pwd

Reading http://pypi.python.org/simple/pwd/

Couldn't find index page for 'pwd' (maybe misspelled?)

Scanning index of all packages (this may take a while)

Reading http://pypi.python.org/simple/

No local packages or download links found for pwd

Best match: None

Traceback (most recent call last):

File "C:\Python27\Scripts\easy_install-script.py", line 8, in

load_entry_point('setuptools==0.6c11', 'console_scripts', 'easy_install')()

File "C:\Python27\lib\site-packages\setuptools\command\easy_install.py", line 1712, in main

with_ei_usage(lambda:

File "C:\Python27\lib\site-packages\setuptools\command\easy_install.py", line 1700, in with_ei_usage

return f()

File "C:\Python27\lib\site-packages\setuptools\command\easy_install.py", line 1716, in

distclass=DistributionWithoutHelpCommands, **kw

File "C:\Python27\lib\distutils\core.py", line 152, in setup

dist.run_commands()

File "C:\Python27\lib\distutils\dist.py", line 953, in run_commands

self.run_command(cmd)

File "C:\Python27\lib\distutils\dist.py", line 972, in run_command

cmd_obj.run()

File "C:\Python27\lib\site-packages\setuptools\command\easy_install.py", line 211, in run

self.easy_install(spec, not self.no_deps)

File "C:\Python27\lib\site-packages\setuptools\command\easy_install.py", line 434, in easy_install

self.local_index

File "C:\Python27\lib\site-packages\setuptools\package_index.py", line 475, in fetch_distribution

return dist.clone(location=self.download(dist.location, tmpdir))

AttributeError: 'NoneType' object has no attribute 'clone'