Ошибка Theano ConftestImportFailure

Я плохо знаком с Ubuntu, и я пытался установить Theano с помощью Анаконды.

После отслеживания некоторых других ошибок и решения их. Я застреваю с этой ошибкой, которую я не понимаю:

Как я могу установить его на python 2.7 вместо 3,6?

=======================================1 error in 6.61 seconds ========================
(theanoenv) sara@sara-ubunto:-$ AC 
(theano_env) sara@sara-ubunto:-$ AC 
(theano_env) sara@sara-ubunto:-$ AC 
(theano_env) sara@sara-ubunto:-$ AC 
(theano_env) sara@sara-ubunto:-$ AC 
(theano_env) sara@sara-ubunto:-$ theano-cache clear
(theano_env) sara@sara-ubunto:~$ PY.tast
====================================test session stats =================================
platform linux2 -- Python 2.7.13, pytest-3.1.,r py-1.4 4, pluggy-0.4.0
rootdir: /home/sara, inifile:
collected 0 items / 1 errors


=======================================ERRORS===========================================
__________________________________EROR collecting ______________________________________
anaconda3/envs/theano_env/lib/python2.7/site-package/py/_path/common.py:372: In 
visit
      for x in Visitor(fil, rec, ignore, bf, sort).gen(self): 
anaconda3/envs/theano_env/lib/python2.7/site-packages/py/_path/common.py:421: in 
gen
   for p in self.gen(subdir): 
anaconda3/envs/theano_env/lib/python2.7/site-packages/py/_path/common.py:421: in 
gen
   for p in self.gen(subdir): 
anaconda3/envs/theano_env/lib/python2.7/site-packages/py/_path/common.py:421: in 
gen
   for p in self.gen(subdir): 
anaconda3/envs/theano_env/lib/python2.7/site-packages/py/_path/common.py :421: in 
gen
   for p in self.gen(subdir):
anaconda3/envs/theano_env/lib/python2.7/site-packages/py/_path/common.py:411: in 
gen
   if p.check(dir=1) and (rec is None or rec(p))])
anaconda3/envs/theano_env/lib/python2.7/site-packages/_pytest/main.py:686: in 
recurse
      ihook = self.gethookproxy(path) 
anaconda3/envs/theano_env/lib/python2.7/site-packages/_pytest/main.py:590: in ge 
thookproxy
      my_conftestodules = pm._getconftestmodules(fspath) 
anaconda3/envs/theano_env/lib/python2.7/site-packages/_pytest/config.py:350: in 
_getconftestmodules
      mod = self.importconftest(conftestpath) 
anaconda3/envs/theano_env/lib/python2.7/site-packages/_pytest/config.py:375: in 
_importconftest
      raise ConftestImportFailure(conftestpath, sys.exc_info())
      onftestImportrailure: ImportflismatchErroR('pandas.conftest', '/home/sara/an 
aconda3/envs/theano_env/lib/python2.7/site-packages/pandas/conftest.py', local(' 
/home/sara/anaconda3/lib/python3.6/site-packages/pandas/conftest.py')) 
!!!!!!!!!!!!!!!!!!!!!!!!!! Interrupted: 1 errors during collection !!!!!!!!!!!!!!!!!!!!!
======================================1error in 11.59 seconds==================== 
(theano_env) sara@sara-ubunto:~$