Traceback (most recent call last):

 "/usr/lib64/python3.4/random.py", line 253, in choice
i = self._randbelow(len(seq))

 "/usr/lib64/python3.4/random.py", line 230, in _randbelow
r = getrandbits(k)
# 0 <= r < 2**kValueError: number of bits must be greater than zero
Traceback (most recent call last):

 "/opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pip/basecommand.py", line 126, in main
self.run(options, args)

 "/opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pip/commands/install.py", line 223, in run
requirement_set.prepare_files(finder, force_root_egg_info=self.bundle, bundle=self.bundle)

 "/opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pip/req.py", line 961, in prepare_files
self.unpack_url(url, location, self.is_download)

 "/opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pip/req.py", line 1075, in unpack_url
return unpack_file_url(link, location)

 "/opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pip/download.py", line 305, in unpack_file_url
unpack_file(source, location, content_type, link)

 "/opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pip/util.py", line 475, in unpack_file
untar_file(filename, location)

 "/opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pip/util.py", line 442, in untar_file
shutil.copyfileobj(fp, destfp)

 "/opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/shutil.py", line 48, in copyfileobj
buf = fsrc.read(length)AttributeError: 'NoneType' object has no attribute 'read'