Python：通过参数传递在另一个 python 脚本中循环 python 脚本

Question

I am trying to run a py script in loop from another py file with a parameter passing.

I am trying the following:

Script1: 
lst = [12,23,45,67,89]
age_lst = []
for i in lst:
  age_i = os.system("python script_to_run {0}".format(int(i)) )
  age_lst.append(age_i)

Below is the code for script_to_run.py

Script2:script_to_run.py
def age(age:int):
  estimated_val = age+2
  return estimated_val
if __name__=="__main__":
  my_age = int(sys.argv[1])
  final_age = age(age=my_age)
  print(final_age)

Whenever I am running Script 1 where I am calling Script 2 (script_to_run.py) It is running fine but age_lst[] is being populated only with 2.

Expectation is

age_lst = [14,25,47,69,91] <---adding 2 with all elements in age_lst

What I am missing?

Also when I am running the Script1.py from cmd, I am getting error python: can't open file 'script_to_run': [Errno 2] No such file or directory

I am using Windows 10.

Answer 1

os.system runs the program and returns its exit code. Your script writes to standard output, a different beast entirely. Exactly what returns from os.system is OS dependent. On linux for example, its the exit code, limited to 0-255, shifted left with signal information added. Messy.

But since you are converting the output to a string and printing to stdout anyway, just have the parent process read that. The subprocess module has several functions that run programs. run is the modern way.

import subprocess as subp
import sys

lst = [12,23,45,67,89]
age_lst = []
for i in lst:
    proc = subp.run([sys.executable, "script_to_run.py", str(i)],
        stdout=subp.PIPE)
    if proc.returncode == 0:
        print("script returned error")
    else:
        age_lst.append(int(proc.stdout))
print(age_lst)