How do I detect the Python version at runtime? [du

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How do I check what version of Python is running my script? (20 answers)

Closed 2 years ago.

I have a Python file which might have to support Python versions < 3.x and >= 3.x. Is there a way to introspect the Python runtime to know the version which it is running (for example, 2.6 or 3.2.x)?

Answer 1

Here's some code I use with sys.version_info to check the Python installation:

def check_installation(rv):
    current_version = sys.version_info
    if current_version[0] == rv[0] and current_version[1] >= rv[1]:
        pass
    else:
        sys.stderr.write( "[%s] - Error: Your Python interpreter must be %d.%d or greater (within major version %d)\n" % (sys.argv[0], rv[0], rv[1], rv[0]) )
        sys.exit(-1)
    return 0

...

# Calling the 'check_installation' function checks if Python is >= 2.7 and < 3
required_version = (2,7)
check_installation(required_version)

Answer 2

Per sys.hexversion and API and ABI Versioning:

import sys
if sys.hexversion >= 0x3000000:
    print('Python 3.x hexversion %s is in use.' % hex(sys.hexversion))

Answer 3

Since all you are interested in is whether you have Python 2 or 3, a bit hackish but definitely the simplest and 100% working way of doing that would be as follows: python python_version_major = 3/2*2 The only drawback of this is that when there is Python 4, it will probably still give you 3.