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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 content_type(self, lst):
 """ Set the CoRE Link Format ct attribute of the resource. :param lst: the list of CoRE Link Format ct attribute of the resource """

        value = []
        if isinstance(lst, str):
            ct = defines.Content_types[lst]
            self.add_content_type(ct)
        elif isinstance(lst, list):
            for ct in lst:
                self.add_content_type(ct)