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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_score_system(self, grade_system_id):
 """Sets the scoring system. arg: grade_system_id (osid.id.Id):
 the grade system raise: InvalidArgument - ``grade_system_id`` is invalid raise: NoAccess - ``Metadata.isReadOnly()`` is ``true`` *compliance: mandatory -- This method must be implemented.* """

        # Implemented from template for osid.resource.ResourceForm.set_avatar_template
        if self.get_score_system_metadata().is_read_only():
            raise errors.NoAccess()
        if not self._is_valid_id(grade_system_id):
            raise errors.InvalidArgument()
        self._my_map['scoreSystemId'] = str(grade_system_id)