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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_instance_prop(self, attr_name, config_prop, value):
 """Set instance property to a value and add it varz if needed"""

        setattr(self, attr_name, value)

        # add to varz if it is not private
        if not config_prop.exclude_from_varz:
            self.varz[attr_name] = value