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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 upload(sess_id_or_alias, files):
 """ Upload files to user's home folder. \b SESSID: Session ID or its alias given when creating the session. FILES: Path to upload. """

    if len(files) < 1:
        return
    with Session() as session:
        try:
            print_wait('Uploading files...')
            kernel = session.Kernel(sess_id_or_alias)
            kernel.upload(files, show_progress=True)
            print_done('Uploaded.')
        except Exception as e:
            print_error(e)
            sys.exit(1)