Processing in wrap_float_literals() can't work line-by-line, as the
tokenize.unparse() doesn't preserve indentation in this case. E.g.:
$ python -m mpmath --no-ipython
>>> def f():
... return 1.2
...
Traceback (most recent call last):
...
File "<unknown>", line 2
return mpf('1.2')
^^^^^^
IndentationError: expected an indented block after function definition on line 1