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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 _set_subject(self, subject):
 """ sets the subject value for the class instance Args: subject(dict, Uri, str):
 the subject for the class instance """

        # if not subject:
        #     self.subject =
        def test_uri(value):
            """ test to see if the value is a uri or bnode

            Returns: Uri or Bnode """
            # .__wrapped__
            if not isinstance(value, (Uri, BlankNode)):
                try:
                    if value.startswith("_:"):
                        return BlankNode(value)
                    else:
                        return Uri(value)
                except:
                    return BlankNode()
            else:
                return value

        if isinstance(subject, dict):
            self.subject = test_uri(subject['s'])
            if isinstance(subject['o'], list):
                for item in subject['o']:
                    self.add_property(subject['p'],
                                      item)
            else:
                self.add_property(subject['p'],
                                  subject['o'])
        else:
            self.subject = test_uri(subject)