properly start user script written in Python

[Gutsycat]

my_script.py["--param","{HOST.HOST}"]

inside my script.py

#!/usr/bin/env python3
...
...

works fine but I need to start it like this:

/usr/bin/python3["my_script.py","--param","{HOST.HOST}"]

and also delete first line in my_script.py #!/usr/bin/env python3