python multithreading, how can i run multiple operations at once

Question

am trying to sftp to remote machine

with my function

def copyToServer(hostname, username, password, destPath, localPath):
    transport = paramiko.Transport((hostname, 22))
    transport.connect(username=username, password=password)
    sftp = paramiko.SFTPClient.from_transport(transport)
    sftp.put(localPath, destPath)
    sftp.close()
    transport.close()

and i want to copy file to multiple servers in parallel

if have tried this

for i in range(xxx.xxx.xxx.111-xxx.xxx.xxx.210):
    hostname = i
    username = defaultLogin
    password = defaultPassword
    thread = threading.Thread(target=copyToServer, args=(hostname, username, password, destPath, localPath))
    thread.start()

this gave me error

Exception in thread Thread-3:
Traceback (most recent call last):
  File "/usr/lib/python2.7/threading.py", line 801, in __bootstrap_inner
    self.run()
  File "/usr/lib/python2.7/threading.py", line 754, in run
    self.__target(*self.__args, **self.__kwargs)
  File "testi.py", line 56, in copyToServer
    log.write("%s   FAILED    - copying failed    directory at remote machine doesn't exist\r\n" % hostname)
ValueError: I/O operation on closed file

Answer 1

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