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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 get_item_type(self, ttype):
 """ Get a particular item type :param ttype: a string which represents the desired type :rtype: None or the item object """

        for i in self.map_item:
            if TYPE_MAP_ITEM[i.get_type()] == ttype:
                return i.get_item()
        return None