如何检查哪个版本的Python解释器正在运行我的脚本?


当前回答

有六个模块,你可以做到:

import six

if six.PY2:
  # this is python2.x
else:
  # six.PY3
  # this is python3.x

其他回答

尝试使用os。Popen在变量中读取它:

import os
ver = os.popen('python -V').read().strip()
print(ver)

可以这样写:

#!/usr/bin/env/python
import sys
if sys.version_info<(2,6,0):
  sys.stderr.write("You need python 2.6 or later to run this script\n")
  exit(1)

在你的脚本顶部。

请注意,根据脚本中的其他内容,比目标版本更老的python甚至可能无法加载脚本,因此不会报告此错误。作为一种变通方法,您可以在一个脚本中运行上述操作,该脚本导入了更现代的代码。

从命令行(注意大写的“V”):

python -V

这在“man python”中有记录。

从IPython控制台

!python -V

只是为了好玩,下面是在CPython 1.0-3.7b2, Pypy, Jython和Micropython上的一种方法。在现代代码中,这更像是一种新奇的做法。我将其作为http://stromberg.dnsalias.org/~strombrg/pythons/的一部分编写,这是一个脚本,用于在多个版本的python上同时测试一段代码,因此您可以轻松地了解哪些python特性与哪些版本的python兼容:

via_platform = 0
check_sys = 0
via_sys_version_info = 0
via_sys_version = 0
test_sys = 0
try:
    import platform
except (ImportError, NameError):
    # We have no platform module - try to get the info via the sys module
    check_sys = 1

if not check_sys:
    if hasattr(platform, "python_version"):
        via_platform = 1
    else:
        check_sys = 1

if check_sys:
    try:
        import sys
        test_sys = 1
    except (ImportError, NameError):
        # just let via_sys_version_info and via_sys_version remain False - we have no sys module
        pass

if test_sys:
    if hasattr(sys, "version_info"):
        via_sys_version_info = 1
    elif hasattr(sys, "version"):
        via_sys_version = 1
    else:
        # just let via_sys remain False
        pass

if via_platform:
    # This gives pretty good info, but is not available in older interpreters.  Also, micropython has a
    # platform module that does not really contain anything.
    print(platform.python_version())
elif via_sys_version_info:
    # This is compatible with some older interpreters, but does not give quite as much info.
    print("%s.%s.%s" % sys.version_info[:3])
elif via_sys_version:
    import string
    # This is compatible with some older interpreters, but does not give quite as much info.
    verbose_version = sys.version
    version_list = string.split(verbose_version)
    print(version_list[0])
else:
    print("unknown")

你最好的选择可能是这样的:

>>> import sys
>>> sys.version_info
(2, 6, 4, 'final', 0)
>>> if not sys.version_info[:2] == (2, 6):
...    print "Error, I need python 2.6"
... else:
...    from my_module import twoPointSixCode
>>> 

此外,您总是可以在一个简单的try中包装导入,这应该会捕获语法错误。而且,按照@Heikki的观点,这段代码将与更老版本的python兼容:

>>> try:
...     from my_module import twoPointSixCode
... except Exception: 
...     print "can't import, probably because your python is too old!"
>>>