code: def _disassemble(self, lineno_width=3, mark_as_current=False):
          
          fields = []
          # Column: Source code line number
          if lineno_width:
              if self.starts_line is not None:
                  lineno_fmt = "%%%dd" % lineno_width
                  fields.append(lineno_fmt % self.starts_line)
              else:
                  fields.append(' ' * lineno_width)
          # Column: Current instruction indicator
          if mark_as_current:
              fields.append('-->')
          else:
              fields.append('   ')
          # Column: Jump target marker
          if self.is_jump_target:
              fields.append('>>')
          else:
              fields.append('  ')
          # Column: Instruction offset from start of code sequence
          fields.append(repr(self.offset).rjust(4))
          # Column: Opcode name
          fields.append(self.opname.ljust(20))
          # Column: Opcode argument
          if self.arg is not None:
              fields.append(repr(self.arg).rjust(5))
              # Column: Opcode argument details
              if self.argrepr:
                  fields.append('(' + self.argrepr + ')')
          return ' '.join(fields).rstrip()
docs: Format instruction details for inclusion in disassembly output
  
          *lineno_width* sets the width of the line number field (0 omits it)
          *mark_as_current* inserts a '-->' marker arrow as part of the line