code: def zfill(self, width):
          
          if not self.value_no_colors:
              result = self.value_no_colors.zfill(width)
          else:
              result = self.value_colors.replace(self.value_no_colors, self.value_no_colors.zfill(width))
          return self.__class__(result, keep_tags=True)
docs: Pad a numeric string with zeros on the left, to fill a field of the specified width.
  
          The string is never truncated.
  
          :param int width: Length of output string.