Python 橙色3:导入错误：无法导入名称'_变量'；

我试图在我的Mac上使用Orange3，但出现以下错误：

ImportError:无法导入名称“\u变量”

这是我的设置：

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

结果如下：

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'

---

有什么好主意吗？

喜欢建议的作品！谢谢。

\u变量

是一个变量。您是如何安装此软件的？

pip在一个
venv
中的Mac上安装orange3

。是否有任何错误输出？你有？您是否安装了XCode（）？啊，还有一些要求，请参阅@MartijnPieters。谢谢

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}

...