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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 from_yaml(cls, yaml_path, **kwargs):
 """ Create cluster with worker pod spec defined by a YAML file We can start a cluster with pods defined in an accompanying YAML file like the following: .. code-block:: yaml kind: Pod metadata: labels: foo: bar baz: quux spec: containers: - image: daskdev/dask:latest name: dask-worker args: [dask-worker, $(DASK_SCHEDULER_ADDRESS), --nthreads, '2', --memory-limit, 8GB] restartPolicy: Never Examples -------- See Also -------- KubeCluster.from_dict """

        if not yaml:
            raise ImportError("PyYaml is required to use yaml functionality, please install it!")
        with open(yaml_path) as f:
            d = yaml.safe_load(f)
            d = dask.config.expand_environment_variables(d)
            return cls.from_dict(d, **kwargs)