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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 _update_property_keys(cls):
 """Set unspecified property_keys for each ConfigProperty to the name of the class attr"""

        for attr_name, config_prop in cls._iter_config_props():
            if config_prop.property_key is None:
                config_prop.property_key = attr_name