code: def render_docstring(self):
          
          default = (' = ' + str(self.default)) if self.default else ''
          opt = 'optional' if self.is_optional else ''
          can_be = ' '.join(self.possible_values) if self.possible_values else ''
          can_be = 'one of [{}]'.format(can_be) if can_be else ''
          type_ = 'of type "' + str(self.type) + '"'
          res = ' '.join([opt, '"' + self.field + '"', default, type_, can_be, '\n'])
          return res.replace('  ', ' ').lstrip()
docs: make a nice docstring for ipython