docs: def filter_by_slurry(self, slurry, appender="_"):
          """Filters sheet/table by slurry name.
  
          Input is slurry name or list of slurry names, for example 'es030' or
          ["es012","es033","es031"].
  
          Args:
              slurry (str or list of strings): slurry names.
              appender (chr): char that surrounds slurry names.
  
          Returns:
              List of serial_number (ints).
          """
  
          sheet = self.table
          identity = self.db_sheet_cols.id
          exists = self.db_sheet_cols.exists
          cellname = self.db_sheet_cols.cell_name
          search_string = ""
  
          if not isinstance(slurry, (list, tuple)):
              slurry = [slurry, ]
  
          first = True
          for slur in slurry:
              s_s = appender + slur + appender
              if first:
                  search_string = s_s
                  first = False
              else:
                  search_string += "|"
                  search_string += s_s
  
          criterion = sheet.loc[:, cellname].str.contains(
              search_string
          )
          exists = sheet.loc[:, exists] > 0
          sheet = sheet[criterion & exists]
  
          return sheet.loc[:, identity].values.astype(int)