与 /usr/bin/python3.4 /usr/bin/python3 的区别

Question

My question is, what is the difference between /usr/bin/python3.6 and /usr/bin/python3. I am using cronjob for running python script. Script is not running under python 3.4 but it is running under 3.6 version. However whenever I am changing it to /usr/bin/python3 it is also running.

What should I use then in cronjob, exact version like 3.6 or just 3? What is best practice? Thanks.

Answer 1

/usr/bin/python3 is the platform default Python 3 installation. It's often inadvisable to change it because of dependencies that other parts of the system may have on it, so it's often older than the latest release. It's normally a symlink to a specific version, so if you want to know what version it actually is run:

ls -al /usr/bin/python3

If you write scripts that need a later language or library versions than /usr/bin/python3 then you will need to install and specify a specific version to ensure you pick those up.

Much beyond that I doubt it matters too much; most distros backport security fixes to their default Python installation so the only reason to use a newer version is a desire to use the new features.

Answer 2

There is no best or worst practice. It's a different python version. Use whichever works fine.

Answer 3

You can find the New Topics of python3.6 here

Well for your query python3.6 has backward compatibility will all versions lower than 3.6

Here is reference example relaed to literal

# python 3.7.4
>> platform="stackoverflow"
>> print(f"we are on {platform}")
we are on stackoverflow

# python 3.4.3
>> platform="stackoverflow"
>> print(f"we are on {platform}")
  File "main.py", line 1                                                                    
    print(f"we are on {platform}")                                                     
                                ^                                                      
SyntaxError: invalid syntax  

I hope this clarify your doubt