def unpin_variant(self, institute, case, user, link, variant):
LOG.info("<STR_LIT>".format(<EOL>variant['<STR_LIT>']))<EOL>LOG.info("<STR_LIT>""<STR_LIT>")<EOL>updated_case = self.case_collection.find_one_and_update(<EOL>{'<STR_LIT>': case['<STR_LIT>']},<EOL>{'<STR_LIT>': {'<STR_LIT>': variant['<STR_LIT>']}},<EOL>return_document=pymongo.ReturnDocument.AFTER<EOL>)<EOL>self.create_event(<EOL>institute=institute,<EOL>case=case,<EOL>user=user,<EOL>link=link,<EOL>category='<STR_LIT>',<EOL>verb='<STR_LIT>',<EOL>variant=variant,<EOL>subject=variant['<STR_LIT>'],<EOL>)<EOL>return updated_case<EOL>
Create an event for unpinning a variant.

        Arguments:
            institute (dict): A Institute object
            case (dict): Case object
            user (dict): A User object
            link (str): The url to be used in the event
            variant (dict): A variant object

        Returns:
            updated_case(dict)