PEP 492 lists the following under "valid syntax" and yet 3.5.2 raises a SyntaxError:

def foo():
    return await coro()

but this works:

def bar():
    return await (coro())

In 3.5, “await” is an ordinary identifier outside of “async def” functions. You have to use the “async def” syntax to enable it as a special keyword.

>>> async def foo():  # “Async def” enables “await” as a keyword
...     return await coro()  # Valid syntax
... 
>>> async def coro(): pass
... 
>>> def await(c):
...     c.close()  # Avoid RuntimeWarning
...     return "Called await({!r})".format(c)
... 
>>> def bar():  # Ordinary non-PEP-492 function
...     return await (coro())
... 
>>> bar()
'Called await(<coroutine object coro at 0x7fb82c50d410>)'