GenerateEventsFilter(InputWorkspace=ws,
                     OutputWorkspace='filter',
                     InformationWorkspace='info',
                     StartTime=start_time,
                     StopTime=stop_time,
                     TimeInterval=time_interval,
                     TimeTolerance=time_tolerance,
                     UnitOfTime=unit_of_time)
FilterEvents(InputWorkspace=ws,
             SplitterWorkspace='filter',
             OutputWorkspaceBaseName=ws + '_filtered',
             InformationWorkspace='info',
             GroupWorkspaces=True,
             FilterByPulseTime=True,
             OutputWorkspaceIndexedFrom1=True)