code: def getUser(cls, cloud):
          
          try:
              config = d = ConfigDict("cloudmesh.yaml")
  
              d = ConfigDict("cloudmesh.yaml")
  
              #
              # bug: cloud is none when adding a group
              #
  
              config = d["cloudmesh"]["clouds"][cloud]
              credentials = config["credentials"]
              cloud_type = config["cm_type"]
  
              if cloud_type == "openstack":
                  return credentials["OS_USERNAME"]
              else:
                  raise ValueError("getUser for this cloud type not yet "
                                   "supported: {}".format(cloud))
          except Exception as ex:
              Console.error("problem getting user")
docs: gets the username for a specified cloud.
          TODO: works currently only for opensatck.
          :param cloud: the name of the cloud
          :return: