code: def label(self, value):
          
          # Fixed width label formatting
          value = value[:self.pad_size] if self.pad_size else value
          try:
              padding = ' ' * (self.pad_size - len(value)) if self.pad_size else ''
          except TypeError:
              padding = ''
  
          self._formatted = ' {v}{p} '.format(v=value, p=padding)
docs: Set the label and generate the formatted value
          @type   value:      str