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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 _put_subject(self, subject_id, body):
 """ Update a subject for the given subject id. The body is not a list but a dictionary of a single resource. """

        assert isinstance(body, (dict)), "PUT requires body to be dict."

        # subject_id could be a path such as '/asset/123' so quote
        uri = self._get_subject_uri(guid=subject_id)
        return self.service._put(uri, body)