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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 get_all_host_templates(resource_root, cluster_name="default"):
 """ Get all host templates in a cluster. @param cluster_name: Cluster name. @return: ApiList of ApiHostTemplate objects for all host templates in a cluster. @since: API v3 """

  return call(resource_root.get,
      HOST_TEMPLATES_PATH % (cluster_name,),
      ApiHostTemplate, True, api_version=3)