In different circumstances, we need to know the Python version, or more precisely, the Python interpreter version that is executing the Python script file.
sys.version Method to Check Python Version
This version information could be retrieved from
sys.version in the
In Python 2.x
>>> import sys >>> sys.version '2.7.10 (default, May 23 2015, 09:44:00) [MSC v.1500 64 bit (AMD64)]'
or in Python 3.x
>>> import sys >>> sys.version '3.7.0 (v3.7.0:1bf9cc5093, Jun 27 2018, 04:59:51) [MSC v.1914 64 bit (AMD64)]'
sys.version_info Method to Check Python Version
sys.version returns a string containing the human-readable version information of the current Python interpreter. But the information like major release number and micro release number needs extra processing to be derived for further usage in the codes.
sys.version_info solves this problem easily by returning the version information as a named tuple. The version data it returns is,
|Data ||Description |
|Major release number |
|Patch release number |
|Minor release number |
|Serial release number |
>>> import sys >>> sys.version_info sys.version_info(major=2, minor=7, micro=10, releaselevel='final', serial=0)
You could compare the current version with the reference version simply using
>>> import sys >>> sys.version_info >= (2, 7) True >>> sys.version_info >= (2, 7, 11) False
We could add an
assert in the scripts to make sure that the script runs with the requirement of minimal Python version.
import sys assert sys.version_info >= (3, 7)
It will raise an
AssertionError if the interpreter doesn’t meet the version requirement.
Traceback (most recent call last): File "C:\test\test.py", line 4, in <module> assert sys.version_info >= (3, 7) AssertionError
platform.python_version() Method to Check Python Version
python_version() in module returns the Python version as string
>>> from platform import python_version >>> python_version() '3.7.0'
Or similar to
platform also has a method to return the Python version as tuple
(major, minor, patchlevel) of strings -
>>> import platform >>> platform.python_version_tuple() ('3', '7', '0')
six Module Method to Check Python Version
If you only need to check whether the Python version is Python 2.x or Python 3.x, you could use to do the job.
import six if six.PY2: print "Python 2.x" if six.PY3: print("Python 3.x")