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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 create_cluster(resource_root, name, version=None, fullVersion=None):
 """ Create a cluster @param resource_root: The root Resource object. @param name: Cluster name @param version: Cluster CDH major version (eg: "CDH4") - The CDH minor version will be assumed to be the latest released version for CDH4, or 5.0 for CDH5. @param fullVersion: Cluster's full CDH version. (eg: "5.1.1") - If specified, 'version' will be ignored. - Since: v6 @return: An ApiCluster object """

  if version is None and fullVersion is None:
    raise Exception("Either 'version' or 'fullVersion' must be specified")
  if fullVersion is not None:
    api_version = 6
    version = None
  else:
    api_version = 1

  apicluster = ApiCluster(resource_root, name, version, fullVersion)
  return call(resource_root.post, CLUSTERS_PATH, ApiCluster, True,
              data=[apicluster], api_version=api_version)[0]