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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 record_type(values):
 """ Creates a record type field. These serve as the header field on records, identifying them. Usually this field can be only an specific value, but sometimes a small range of codes is allowed. This is specified by the 'values' parameter. While it is possible to set this field as optional, it is expected to be compulsory. :param values: allowed record type codes :return: grammar for the record type field """

    field = basic.lookup(values, name='Record Type (one of %s)' % values)

    return field.setResultsName('record_type')