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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 _generate_trials(self, unresolved_spec, output_path=""):
 """Generates Trial objects with the variant generation process. Uses a fixed point iteration to resolve variants. All trials should be able to be generated at once. See also: `ray.tune.suggest.variant_generator`. Yields: Trial object """


        if "run" not in unresolved_spec:
            raise TuneError("Must specify `run` in {}".format(unresolved_spec))
        for _ in range(unresolved_spec.get("num_samples", 1)):
            for resolved_vars, spec in generate_variants(unresolved_spec):
                experiment_tag = str(self._counter)
                if resolved_vars:
                    experiment_tag += "_{}".format(resolved_vars)
                self._counter += 1
                yield create_trial_from_spec(
                    spec,
                    output_path,
                    self._parser,
                    experiment_tag=experiment_tag)