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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def sftp_upload_window_size_set(srv,file, method_to_call='put'):
    '''
    sets config for uploading files with pysftp
    '''
    channel = srv.sftp_client.get_channel()
    channel.lock.acquire()
    channel.out_window_size += os.stat(file).st_size * 1.1   # bit more bytes incase packet loss
    channel.out_buffer_cv.notifyAll()
    channel.lock.release()