我应该在Python v2.6.2中导入哪些功能？

我开始学习Python，但我不得不使用v2.6.2解释器

我希望尽可能接近Python 3，例如，使用新的

print

函数，“true”除法，等等

from __future__ import division
from __future__ import print_function
print(1/2, file=sys.stderr) # 0.5

我还应该从

\uuuuuuuuuuuuuuuuuuuuuu

导入哪些其他功能

---

我想我可以做一个常规的导入，但是当我升级到更高的版本时，我会有不同的行为（v2.7可能在

\uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuu

>>> import __future__
>>> __future__.all_feature_names
['nested_scopes', 'generators', 'division', 'absolute_import', 'with_statement', 'print_function', 'unicode_literals']
>>> __future__.unicode_literals
_Feature((2, 6, 0, 'alpha', 2), (3, 0, 0, 'alpha', 0), 131072)

Python2.6已经启用了大多数功能，因此可以从
division
、
print\u function
、
absolute\u import
和
unicode\u literals
中进行选择

不，
import\uuuuu future\uuuuu
不会像你想象的那样工作。当您使用
from\uuuuuu future\uuuuuu导入某物
表单作为文件中的第一条语句时，这才是神奇的。更多信息，请参阅

当然，无论您从
\uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuu

我还应该从
\uuuuuuuuuuuuuuuuuuuuuu
导入哪些其他功能

为了获得最新的行为，您当然应该导入所提供的所有
\uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuu。（按照系统的设置方式，旧功能即使始终打开，也不会被删除。）

请注意，
import\uuuuu future\uuuuu
将不会给您提供一切，也不会
from\uuuuu future\uuuuu导入*
。来自。。。导入…
语法是针对
\uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuu>的特殊情况（这就是它的工作原理），但是
\uuuuuuuuuuuuuuuuu。但是，这样做会让您知道实际的功能名称，以及有关何时（或预期）将其设置为默认值以及何时可用的信息

>>> [
...     name for name in __future__.all_feature_names if
...     getattr(__future__, name).optional <=
...     sys.version_info <
...     getattr(__future__, name).mandatory
... ]

['division', 'print_function', 'unicode_literals']

>[
…未来中名称的名称。如果
…getattr（\uuuuu future\uuuuuu，name）。可选。你确定这是明智的吗？如果你被迫使用Python 2.x，并且开始以Python 3.x的风格编写代码，那么强迫你使用2.x的人不会抱怨吗？@DavidHeffernan:不，我可以随心所欲地编写脚本。只是我在一台安装了Python v2.6.2的旧计算机上，另外还安装了Python v3这似乎不是一个选项。安装Python3完全是一个问题option@Frank那就安装一个可移植的Python 3.x吧。你不需要这样安装任何东西，只要把它复制到你的桌面上，然后从那里运行即可。
from\uuuuuuuuuuuuuuuuu\import
是一个future语句，而不是import语句——它有特殊的语义。
import_uuufuture_uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuu。@KarlKnechtel或者Nick Coglan或者Raymond Hettinger反对使用它，说将它包含在
\uuuu future\uuuuuu
中是一个错误。我不记得它是在这里还是在博客帖子中。我只是使用了那个链接，因为我找不到我现在正在思考的那个链接。确实，由此产生的行为与3.x.U不太像无论如何，在输入/输出之外的任何地方使用UTF-8编码的ByTestRing都是一个坏主意。至少它以这种方式大声中断，而不是给出错误的结果，或者在某些机器上中断，而不是在其他机器上中断。