code: def _indent(self, textstr, indent_level=4):
          
          if sys.hexversion >= 0x03030000:
              return textwrap.indent(textstr, ' ' * indent_level)
          else:
              lst = [(' ' * indent_level + x) for x in textstr.split('\n')]
              return '\n'.join(lst)
docs: Indent a string.
  
          Textwrap's indent method only exists for 3.3 or above.  In 2.7 we have
          to fake it.
  
          Parameters
          ----------
          textstring : str
              String to be indented.
          indent_level : str
              Number of spaces of indentation to add.
  
          Returns
          -------
          str
              Possibly multi-line string indented by the specified amount.