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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 loads(self, config_str, as_defaults=False):
 """ Load configuration values from the specified source string. Args: config_str: as_defaults (bool):
 if ``True``, contents of ``source`` will be treated as schema of configuration items. """

        self._rw.load_config_from_string(self._config, config_str, as_defaults=as_defaults)