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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 isrc(name=None):
 """ Creates the grammar for an ISRC code. ISRC stands for International Standard Recording Code, which is the standard ISO 3901. This stores information identifying a particular recording. :param name: name for the field :return: grammar for an ISRC field """


    if name is None:
        name = 'ISRC Field'

    field = _isrc_short(name) | _isrc_long(name)

    field.setName(name)

    return field.setResultsName('isrc')