查看版本

$ python --version

sys 模块内查询

>>> import sys
>>> sys.version_info
sys.version_info(major=3, minor=6, micro=8, releaselevel='final', serial=0)
>>> sys.version
'3.6.8 |Anaconda custom (64-bit)| (default, Dec 29 2018, 19:04:46) \n[GCC 4.2.1 Compatible Clang 4.0.1 (tags/RELEASE_401/final)]'
>>>

**优先考虑 Python3 版本！**