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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 list(self, link_type, product, identifierType=None):
 """ Retrieve list of linked products :param link_type: type of link, one of 'cross_sell', 'up_sell', 'related' or 'grouped' :param product: ID or SKU of product :param identifierType: Defines whether the product or SKU value is passed in the "product" parameter. :return: `list` of `dict` """

        return self.call('catalog_product_link.list',
                         [link_type, product, identifierType])