docs: def _discretize_check(self, table, att, col):
          '''
          Replaces the value with an appropriate interval symbol, if available.
          '''
          label = "'%s'" % col
          if table in self.discr_intervals and att in self.discr_intervals[table]:
              intervals = self.discr_intervals[table][att]
              n_intervals = len(intervals)
  
              prev_value = None
              for i, value in enumerate(intervals):
  
                  if i > 0:
                      prev_value = intervals[i - 1]
  
                  if not prev_value and col <= value:
                      label = "'=<%.2f'" % value
                      break
                  elif prev_value and col <= value:
                      label = "'(%.2f;%.2f]'" % (prev_value, value)
                      break
                  elif col > value and i == n_intervals - 1:
                      label = "'>%.2f'" % value
                      break
          else:
              # For some reason using [ and ] crashes TreeLiker
              label = label.replace('[', 'I')
              label = label.replace(']', 'I')
  
          return label