code: def set_error_pages(self, codes_map=None, common_prefix=None):
          
          statuses = [403, 404, 500]
  
          if common_prefix:
              if not codes_map:
                  codes_map = {code: '%s.html' % code for code in statuses}
  
              for code, filename in codes_map.items():
                  codes_map[code] = os.path.join(common_prefix, filename)
  
          for code, filepath in codes_map.items():
              self.set_error_page(code, filepath)
  
          return self._section
docs: Add an error pages for managed 403, 404, 500 responses.
  
          Shortcut for ``.set_error_page()``.
  
          :param dict codes_map: Status code mapped into an html filepath or
              just a filename if common_prefix is used.
  
              If not set, filename containing status code is presumed: 400.html, 500.html, etc.
  
          :param str|unicode common_prefix: Common path (prefix) for all files.