Sorry, I didn't make the question clear yesterday.
My operating system is Windows and the compiler used is VS2019. My project address: https://github.com/twoone-3/BDSpyrunner
When I use Python.dll to import Python files, the program is stuck. After checking, I found that as long as I use multi-threading, the program will be stuck. Of course, this Python file can be directly run by Python.exe, but from  My program cannot run normally when calling Python.dll

The file:
import threading
import time
 
def worker():
     print "worker"
     time.sleep( 1 )
     return
 
for i in xrange ( 5 ):
     t = threading.Thread(target = worker)
     t.start()