orange3: ImportError: невозможно импортировать имя '_variable'

Question

Я пытаюсь использовать Orange3 на своем Mac, но я получаю эту ошибку: ImportError: cannot import name '_variable'.

Это моя установка:

$ cd orange_playground 
$ virtualenv -p python3 venv 
$ pip install orange3 
$ source venv/bin/activate 
$ python 

Выход следующим образом:

Python 3.4.2 (default, Oct 8 2014, 19:29:52) 
[GCC 4.2.1 Compatible Apple LLVM 6.0 (clang-600.0.51)] on darwin 
Type "help", "copyright", "credits" or "license" for more information. 
>>> import Orange 
Traceback (most recent call last): 
    File "<stdin>", line 1, in <module> 
    File "orange_playground/venv/lib/python3.4/site-packages/Orange/__init__.py", line 11, in <module> 
    from .misc.lazy_module import _LazyModule 
    File "orange_playground/venv/lib/python3.4/site-packages/Orange/misc/__init__.py", line 3, in <module> 
    from .distmatrix import DistMatrix 
    File "orange_playground/venv/lib/python3.4/site-packages/Orange/misc/distmatrix.py", line 3, in <module> 
    from Orange.data import Table, StringVariable, Domain 
    File "orange_playground/venv/lib/python3.4/site-packages/Orange/data/__init__.py", line 4, in <module> 
    from .variable import * 
    File "orange_playground/venv/lib/python3.4/site-packages/Orange/data/variable.py", line 11, in <module> 
    from Orange.data import _variable 
ImportError: cannot import name '_variable' 

Первые строки кода из orange_playground/venv/lib/python3.4/site-packages/Orange/data/variable.py:

import collections 
import re 

from datetime import datetime, timedelta, timezone 
from numbers import Number, Real, Integral 
from math import isnan, floor 
from pickle import PickleError 

import numpy as np 

from Orange.data import _variable 
from Orange.util import Registry, color_to_hex, hex_to_color 

__all__ = ["Unknown", "MISSING_VALUES", "make_variable", "is_discrete_values", 
      "Value", "Variable", "ContinuousVariable", "DiscreteVariable", 
      "StringVariable", "TimeVariable"] 


# For storing unknowns 
Unknown = ValueUnknown = float("nan") 
# For checking for unknowns 
MISSING_VALUES = {np.nan, "?", "nan", ".", "", "NA", "~", None} 

... 

Любые идеи, что делать?

Answer 1

Installing Orange3 from source как @MartijnPieters Предлагаемые работы! Благодарю.