code: def _get_property_columns(tabletype, columns):
      
      from ligo.lw.lsctables import gpsproperty as GpsProperty
      # get properties for row object
      rowvars = vars(tabletype.RowType)
      # build list of real column names for fancy properties
      extracols = {}
      for key in columns:
          prop = rowvars[key]
          if isinstance(prop, GpsProperty):
              extracols[key] = (prop.s_name, prop.ns_name)
      return extracols
docs: Returns list of GPS columns required to read gpsproperties for a table
  
      Examples
      --------
      >>> _get_property_columns(lsctables.SnglBurstTable, ['peak'])
      ['peak_time', 'peak_time_ns']