Python2 vs Python3

[RobD]

Something is puzzling me.
I have a RPi 4b with the latest version of Raspberry OS running Domoticz 2020.2.
On the Pi, Python2 and Python3 are installed.
I stumbled into a problem because a Python script which was developed in Python3 did not run as a script_time_xxx.py.
Looking into this I discovered that when Domoticz starts a script it is run on Python2 even though I have included the Shebang

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#!/usr/bin/env python3

can anybody help me out?

[Thorgal789]

On my side have right problem with python, so I run shell script with domoticz, and the shell script run the python script.
It solve lot of issues.

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#!/bin/bash

python3 /home/pi/hp/play_radio.py > /dev/null 2>&1 &

exit 0

[RobD]

sure, I have a comparable workaround.
the thing is that I like to understand the cause of the problem

[erem]

from the command line

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which python3

my result : /usr/bin/python3

then try changing the shebang to

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#!/usr/bin/python3

[waaren]

sure, I have a comparable workaround.
the thing is that I like to understand the cause of the problem

The Shebang! line is ignored when the code is parsed as parm to the controlling interpreter
Consider this Python source with a Shebang!

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#!/usr/bin/python3

import sys

print(sys.version)

# Force use of Python3

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python3 ./version.py      
3.7.3 (default, Jul 25 2020, 13:03:44)
[GCC 8.3.0]

# Force use of Python2

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python2 ./version.py  
2.7.16 (default, Oct 10 2019, 22:02:15)
[GCC 8.3.0]

# Relying on Shebang! for choosing the right interpreter

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./version.py    

3.7.3 (default, Jul 25 2020, 13:03:44)
[GCC 8.3.0]