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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 yaml_dump(dict_to_dump):
 """ Dump the dictionary as a YAML document. :param dict_to_dump: Data to be serialized as YAML :type dict_to_dump: dict :return: YAML document :rtype: str """

    yaml.SafeDumper.add_representer(OrderedDict, _dict_representer)
    return yaml.safe_dump(dict_to_dump, default_flow_style=False)