Fix format string for Python 3.4/3.5
@@ -547,7 +547,7 @@ class Parser(object):
tok = symbol.recognizer(context, input_str, position)
except TypeError as e:
raise TypeError(
- f'In recognizer for "{symbol}": {e}') from e
+ 'In recognizer for "{}": {}'.format(symbol, e)) from e
additional_data = ()
if type(tok) is tuple:
