code: def source(self):
          
          full_src = self._source[self._slice]
  
          def is_empty_or_comment(line):
              return line.strip() == '' or line.strip().startswith('#')
  
          filtered_src = dropwhile(is_empty_or_comment, reversed(full_src))
          return ''.join(reversed(list(filtered_src)))
docs: Return the source code for the definition.