Mercurial 2.1.1 installation error

gistfile1.txt

~ $ mktmpenv 
Using real prefix '/Library/Frameworks/Python.framework/Versions/2.7'
New python executable in 9c0e1be03bb8d654/bin/python
Installing distribute....................................................................................................................................................................................done.
virtualenvwrapper.user_scripts creating /Users/dhellmann/Envs/9c0e1be03bb8d654/bin/predeactivate
virtualenvwrapper.user_scripts creating /Users/dhellmann/Envs/9c0e1be03bb8d654/bin/postdeactivate
virtualenvwrapper.user_scripts creating /Users/dhellmann/Envs/9c0e1be03bb8d654/bin/preactivate
virtualenvwrapper.user_scripts creating /Users/dhellmann/Envs/9c0e1be03bb8d654/bin/postactivate
virtualenvwrapper.user_scripts creating /Users/dhellmann/Envs/9c0e1be03bb8d654/bin/get_env_details
This is a temporary environment. It will be deleted when you run 'deactivate'.
(9c0e1be03bb8d654)9c0e1be03bb8d654 $ pip install Mercurial
Downloading/unpacking Mercurial
  Downloading mercurial-2.1.1.tar.gz (3.3Mb): 3.3Mb downloaded
  Running setup.py egg_info for package Mercurial
    Traceback (most recent call last):
      File "<string>", line 14, in <module>
      File "/Users/dhellmann/Envs/9c0e1be03bb8d654/build/Mercurial/setup.py", line 457, in <module>
        version = version.splitlines()[0]
    AttributeError: 'list' object has no attribute 'splitlines'
    Complete output from command python setup.py egg_info:
    Traceback (most recent call last):

  File "<string>", line 14, in <module>

  File "/Users/dhellmann/Envs/9c0e1be03bb8d654/build/Mercurial/setup.py", line 457, in <module>

    version = version.splitlines()[0]

AttributeError: 'list' object has no attribute 'splitlines'

----------------------------------------
Command python setup.py egg_info failed with error code 1
Storing complete log in /Users/dhellmann/.pip/pip.log