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How to create a new console in Python to print message

I make a python script running in the console, and I want to create another console for printing important messages without running another python script to do that.
I first tried to use win32console.AllocConsole() directly, but it got Access is denied
(Seemingly because one process can attach to at most one console according to the docs).
So I tried creating a new process by using multiprocessing :
import sys, os
import win32api, win32con, win32console
import multiprocessing
def ShowConsole():
win32console.FreeConsole()
win32console.AllocConsole()
sys.stdout = open("CONOUT$", "w")
sys.stderr = open("CONOUT$", "w")
print("Test")
os.system("pause")
if __name__ == '__main__':
p = multiprocessing.Process(target=ShowConsole)
p.start()
But when I ran the code in Powershell, it exited directly with no message while no new console is created.
None of the possible solutions I found in stackoverflow works for me. What should I do?
Update: It turns out that it is because multiprocessing.Process fails to call ShowConsole function. I use multiprocessing.dummy.Process as the alternative and it works as expected.
The reason why multiprocessing.Process fails to call target is still unclear.

There's nothing wrong with your example above, it pops the console as shown below. I added a "hello" in the main section to differentiate.
But since you want to values from the first console to the second,
here's a better example. Utilize put/get to pass the information from the first console to the second console.
import win32console
import multiprocessing
import time
def secondconsole(output):
win32console.FreeConsole()
win32console.AllocConsole()
while True:
print(output.get())
if __name__ == "__main__":
output = multiprocessing.Queue()
multiprocessing.Process(target=secondconsole, args=[output]).start()
while True:
print("Hello World")
output.put("Hello to second console") #here you will provide the data to the second console
time.sleep(3) #sleep for 3 seconds just for testing

It looks like the issue might be with the way you are trying to open the console using sys.stdout and sys.stderr. Try using the following code instead:
import sys, os
import win32api, win32con, win32console
import multiprocessing
def ShowConsole():
win32console.FreeConsole()
win32console.AllocConsole()
os.dup2(win32console.GetStdHandle(win32console.STD_OUTPUT_HANDLE), sys.stdout.fileno())
os.dup2(win32console.GetStdHandle(win32console.STD_ERROR_HANDLE), sys.stderr.fileno())
print("Test")
os.system("pause")
if __name__ == '__main__':
p = multiprocessing.Process(target=ShowConsole)
p.start()

Creating a Flag file

I'm relatively new to python so please forgive early level understanding!
I am working to create a kind of flag file. Its job is to monitor a Python executable, the flag file is constantly running and prints "Start" when the executable started, "Running" while it runs and "Stop" when its stopped or crashed, if a crash occurs i want it to be able to restart the script. so far i have this down for the Restart:
from subprocess import run
from time import sleep
# Path and name to the script you are trying to start
file_path = "py"
restart_timer = 2
def start_script():
try:
# Make sure 'python' command is available
run("python "+file_path, check=True)
except:
# Script crashed, lets restart it!
handle_crash()
def handle_crash():
sleep(restart_timer) # Restarts the script after 2 seconds
start_script()
start_script()
how can i implement this along with a flag file?

Not sure what you mean with "flag", but this minimally achieves what you want.
Main file main.py:
import subprocess
import sys
from time import sleep
restart_timer = 2
file_path = 'sub.py' # file name of the other process
def start():
try:
# sys.executable -> same python executable
subprocess.run([sys.executable, file_path], check=True)
except subprocess.CalledProcessError:
sleep(restart_timer)
return True
else:
return False
def main():
print("starting...")
monitor = True
while monitor:
monitor = start()
if __name__ == '__main__':
main()
Then the process that gets spawned, called sub.py:
from time import sleep
sleep(1)
print("doing stuff...")
# comment out to see change
raise ValueError("sub.py is throwing error...")
Put those files into the same directory and run it with python main.py
You can comment out the throwing of the random error to see the main script terminate normally.
On a larger note, this example is not saying it is a good way to achieve the quality you need...

Redirect output from a multiprocess?

I am having trouble logging everything that happens in a called multi processed module.
Script: mainScript.py
import multiprocessing
python_file = A different python file
def main():
module = __import__(python_file)
p = multiprocessing.Process(target=getattr(module, 'main'), args=())
p.start()
step_timeout = 20
p.join(step_timeout)
Script: A different python file
import os
def main():
print('I am a different python script')
os.system('dir').read()
os.system("call C:\\test.bat")
return
I am having trouble logging the output from the batch files that are called as well as the result of os.system(command).read().
I know you can log everything that run through a python script doing something like this...
python mainScript.py >> logFile.txt
Is it possible I can do something like this with the multiprocessing output?
p = multiprocessing.Process(target=getattr(module, 'main'), args=()) >> logFile.txt
If so, will it also capture the output of the batch scripts?
Is it possible to redirect everything that is printed in my called process to the main process?

AttributeError("module 'name' has no attribute 'def name'",)

I'm creating a virtual OS with different files, like boot.py and Run.py
It worked for a while until I typed this in:
if Run.run == 0:
error()
else:
start()
There is no errors saying about it like red lines or any. Now I get this error:
AttributeError("module 'boot' has no attribute 'bootup'",)
Here's the code:
boot.py:
#Imports
import Run
#Varibles
name = "PyOS"
version = 1
creator = "© Dragon Softwares"
def bootup(run):
if Run.run == 0:
error()
else:
start()
def start():
print("Starting PyOS")
print("Version ", version)
def error():
print("Please Run 'Run.py' To bootup the system")
bootup()
Run.py:
#Imports
import time
import boot
#Varibles
run = 0
def main():
run = 1
time.sleep(0.1)
boot.bootup
main()

You have a circular import. Don't have boot import Run and vice-versa.
What happens now is:
Run.py is executed as the __main__ module.
The line import boot is reached and executed.
boot has not been imported before, so boot.py is found and loaded to be the boot module.
The line import Run is reached and executed.
Run has not been imported before, so Run.py is found and loaded to be the Run module. Note: that Run.py is also used for __main__ does not matter here.
The line import boot is reached and executed.
boot is already being imported, so it used to set the name boot in the Run module
Various other names are set in the Run module namespace (run and main).
The line main() is reached and executed
The main() function references boot.bootup, which doesn't exist yet, because the boot module top-level code never reached the def bootup(run): line.
Instead of importing Run, pass the run value as a parameter to the boot function:
def main():
run = 1
time.sleep(0.1)
boot.bootup(run)
Also, don't call bootup() at the end of the boot module. That function call will be executed when you import boot, and makes no sense there. If you want to present an error message, use a if __name__ == '__main__': guard:
if __name__ == '__main__':
import sys
error()
sys.exit(1)
The if test will only ever be true if you ran boot.py as the script.

return value from one python script to another

I have two files: script1.py and script2.py. I need to invoke script2.py from script1.py and return the value from script2.py back to script1.py. But the catch is script1.py actually runs script2.py through os.
script1.py:
import os
print(os.system("script2.py 34"))
script2.py
import sys
def main():
x="Hello World"+str(sys.argv[1])
return x
if __name__ == "__main__":
x= main()
As you can see, I am able to get the value into script2, but not back to script1. How can I do that? NOTE: script2.py HAS to be called as if its a commandline execution. Thats why I am using os.

Ok, if I understand you correctly you want to:
pass an argument to another script
retrieve an output from another script to original caller
I'll recommend using subprocess module. Easiest way would be to use check_output() function.
Run command with arguments and return its output as a byte string.
Sample solution:
script1.py
import sys
import subprocess
s2_out = subprocess.check_output([sys.executable, "script2.py", "34"])
print s2_out
script2.py:
import sys
def main(arg):
print("Hello World"+arg)
if __name__ == "__main__":
main(sys.argv[1])

The recommended way to return a value from one python "script" to another is to import the script as a Python module and call the functions directly:
import another_module
value = another_module.get_value(34)
where another_module.py is:
#!/usr/bin/env python
def get_value(*args):
return "Hello World " + ":".join(map(str, args))
def main(argv):
print(get_value(*argv[1:]))
if __name__ == "__main__":
import sys
main(sys.argv)
You could both import another_module and run it as a script from the command-line. If you don't need to run it as a command-line script then you could remove main() function and if __name__ == "__main__" block.
See also, Call python script with input with in a python script using subprocess.