Detailed explanation of multithreading in Python

import threading, zipfile 
class AsyncZip(threading.Thread): 
  def __init__(self, infile, outfile): 
    threading.Thread.__init__(self) 
    self.infile = infile 
    self.outfile = outfile 
  def run(self): 
    f = zipfile.ZipFile(self.outfile, 'w', zipfile.ZIP_DEFLATED) 
    f.write(self.infile) 
    f.close() 
    print('Finished background zip of:', self.infile) 
 
background = AsyncZip('mydata.txt', 'myarchive.zip') 
background.start() 
print('The main program continues to run in foreground.') 
 
background.join()  # Wait for the background task to finish 
print('Main program waited until background was done.')

The main program continues to run in foreground. 
Finished background zip of: mydata.txt 
Main program waited until background was done. 
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