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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 delete_all(config=None):
 """ Deletes all hosts from ssh config. """

    storm_ = get_storm_instance(config)

    try:
        storm_.delete_all_entries()
        print(get_formatted_message('all entries deleted.', 'success'))
    except Exception as error:
        print(get_formatted_message(str(error), 'error'), file=sys.stderr)
        sys.exit(1)