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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 _override_data(self, overrides):
 """ This method overrides data members of the class, but does not allow for adding new members. :param overrides: Dict with data overrides. """

        if overrides is not None:
            for name, val in overrides.items():
                self.log.debug('Trying to override initial data (%s=%s)', name, val)
                if name not in dir(self):
                    raise AttributeError(
                        'Can not override non-existing attribute'
                        '\'{}\' of class \'{}\'.'.format(name, type(self).__name__))

                setattr(self, name, val)