code: def get_query_string(environ):
      
      qs = wsgi_get_bytes(environ.get("QUERY_STRING", ""))
      # QUERY_STRING really should be ascii safe but some browsers
      # will send us some unicode stuff (I am looking at you IE).
      # In that case we want to urllib quote it badly.
      return try_coerce_native(url_quote(qs, safe=":&%=+$!*'(),"))
docs: Returns the `QUERY_STRING` from the WSGI environment.  This also takes
      care about the WSGI decoding dance on Python 3 environments as a
      native string.  The string returned will be restricted to ASCII
      characters.
  
      .. versionadded:: 0.9
  
      :param environ: the WSGI environment object to get the query string from.