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")

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

从stdlib中使用平台的python_version:

from platform import python_version
print(python_version())

# 3.9.2

下面是一个简短的命令行版本，它可以直接退出(方便脚本和自动执行):

python -c "print(__import__('sys').version)"

或者只是大调、小调和微调:

python -c "print(__import__('sys').version_info[:1])" # (2,)
python -c "print(__import__('sys').version_info[:2])" # (2, 7)
python -c "print(__import__('sys').version_info[:3])" # (2, 7, 6)

如果你想检测python 3之前的版本，但不想导入任何东西…

.．.你可以(ab)使用列表理解范围的变化，并在一个表达式中完成:

is_python_3_or_above = (lambda x: [x for x in [False]] and None or x)(True)

from sys import version_info, api_version, version, hexversion

print(f"sys.version: {version}")
print(f"sys.api_version: {api_version}")
print(f"sys.version_info: {version_info}")
print(f"sys.hexversion: {hexversion}")

输出

sys。版本:3.6.5 (v3.6.5:f59c0932b4, march 28 2018, 17:00:18) [MSC .1900 64位(AMD64)] sys。api_version: 1013 sys。version_info: sys。Version_info (major=3, minor=6, micro=5, releaslevel ='final'， serial=0) sys。hexversion: 50726384