docs: def getSeverity(self, severity_name, projectarea_id=None,
                      projectarea_name=None):
          """Get :class:`rtcclient.models.Severity` object by its name
  
          At least either of `projectarea_id` and `projectarea_name` is given
  
          :param severity_name: the severity name
          :param projectarea_id: the :class:`rtcclient.project_area.ProjectArea`
              id
          :param projectarea_name: the project area name
          :return: the :class:`rtcclient.models.Severity` object
          :rtype: rtcclient.models.Severity
          """
  
          self.log.debug("Try to get <Severity %s>", severity_name)
          if not isinstance(severity_name,
                            six.string_types) or not severity_name:
              excp_msg = "Please specify a valid Severity name"
              self.log.error(excp_msg)
              raise exception.BadValue(excp_msg)
  
          severities = self._getSeverities(projectarea_id=projectarea_id,
                                           projectarea_name=projectarea_name,
                                           severity_name=severity_name)
  
          if severities is not None:
              severity = severities[0]
              self.log.info("Find <Severity %s>", severity)
              return severity
  
          self.log.error("No Severity named %s", severity_name)
          raise exception.NotFound("No Severity named %s" % severity_name)