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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 _validate(self):
 """ Run the validators found in self._defaults on all the corresponding values. Raises: ValueError: If the configuration contains an invalid configuration value. """

        errors = []
        for k in self._defaults.keys():
            try:
                validator = self._defaults[k]['validator']
                if validator is not None:
                    self[k] = validator(self[k])
            except ValueError as e:
                errors.append('\t{}: {}'.format(k, six.text_type(e)))

        if errors:
            raise ValueError(
                'Invalid configuration values were set: \n{}'.format('\n'.join(errors)))