def post(self, path):
        assert self.get_body_arguments("appmode_action")[0] == "delete"
        path = path.strip('/')
        self.log.info('Appmode deleting: %s', path)

        # delete session, including the kernel
        sm = self.session_manager
        if gen.is_coroutine_function(sm.get_session):
            s = yield sm.get_session(path=path)
        else:
            s = sm.get_session(path=path)
        if gen.is_coroutine_function(sm.delete_session):
            yield sm.delete_session(session_id=s['id'])
        else:
            sm.delete_session(session_id=s['id'])

        # delete tmp copy
        cm = self.contents_manager
        cm.delete(path)
        self.finish()

    #=========================================================================== 

def is_tornado_coroutine(func):
    """
    Return whether *func* is a Tornado coroutine function.
    Running coroutines are not supported.
    """
    if 'tornado.gen' not in sys.modules:
        return False
    gen = sys.modules['tornado.gen']
    if not hasattr(gen, "is_coroutine_function"):
        # Tornado version is too old
        return False
    return gen.is_coroutine_function(func) 

def test_is_coroutine_function(self):
        self.finished = True

        def f():
            yield gen.moment

        coro = gen.coroutine(f)
        self.assertFalse(gen.is_coroutine_function(f))
        self.assertTrue(gen.is_coroutine_function(coro))
        self.assertFalse(gen.is_coroutine_function(coro())) 

def test_is_coroutine_function(self):
        self.finished = True

        def f():
            yield gen.moment

        coro = gen.coroutine(f)
        self.assertFalse(gen.is_coroutine_function(f))
        self.assertTrue(gen.is_coroutine_function(coro))
        self.assertFalse(gen.is_coroutine_function(coro())) 

def is_tornado_coroutine(func):
    """
    Return whether *func* is a Tornado coroutine function.
    Running coroutines are not supported.
    """
    if 'tornado.gen' not in sys.modules:
        return False
    gen = sys.modules['tornado.gen']
    if not hasattr(gen, "is_coroutine_function"):
        # Tornado version is too old
        return False
    return gen.is_coroutine_function(func) 

def is_tornado_coroutine(func):
    """
    Return whether *func* is a Tornado coroutine function.
    Running coroutines are not supported.
    """
    if 'tornado.gen' not in sys.modules:
        return False
    gen = sys.modules['tornado.gen']
    if not hasattr(gen, "is_coroutine_function"):
        # Tornado version is too old
        return False
    return gen.is_coroutine_function(func) 

def is_tornado_coroutine(func):
    """
    Return whether *func* is a Tornado coroutine function.
    Running coroutines are not supported.
    """
    if 'tornado.gen' not in sys.modules:
        return False
    gen = sys.modules['tornado.gen']
    if not hasattr(gen, "is_coroutine_function"):
        # Tornado version is too old
        return False
    return gen.is_coroutine_function(func) 

def test_is_coroutine_function(self):
        self.finished = True

        def f():
            yield gen.moment

        coro = gen.coroutine(f)
        self.assertFalse(gen.is_coroutine_function(f))
        self.assertTrue(gen.is_coroutine_function(coro))
        self.assertFalse(gen.is_coroutine_function(coro())) 

def is_tornado_coroutine(func):
    """
    Return whether *func* is a Tornado coroutine function.
    Running coroutines are not supported.
    """
    if 'tornado.gen' not in sys.modules:
        return False
    gen = sys.modules['tornado.gen']
    if not hasattr(gen, "is_coroutine_function"):
        # Tornado version is too old
        return False
    return gen.is_coroutine_function(func) 

def is_tornado_coroutine(func):
    """
    Return whether *func* is a Tornado coroutine function.
    Running coroutines are not supported.
    """
    if 'tornado.gen' not in sys.modules:
        return False
    gen = sys.modules['tornado.gen']
    if not hasattr(gen, "is_coroutine_function"):
        # Tornado version is too old
        return False
    return gen.is_coroutine_function(func) 

def is_tornado_coroutine(func):
    """
    Return whether *func* is a Tornado coroutine function.
    Running coroutines are not supported.
    """
    if 'tornado.gen' not in sys.modules:
        return False
    gen = sys.modules['tornado.gen']
    if not hasattr(gen, "is_coroutine_function"):
        # Tornado version is too old
        return False
    return gen.is_coroutine_function(func) 

def test_retry(self):
        assert gen.is_coroutine_function(_retryable_coroutine)
        thing = NoIOErrorAfterCount(5)
        yield _retryable_coroutine(thing)
        assert thing.counter == thing.count 

def test_stop_after_attempt(self):
        assert gen.is_coroutine_function(_retryable_coroutine)
        thing = NoIOErrorAfterCount(2)
        try:
            yield _retryable_coroutine_with_2_attempts(thing)
        except RetryError:
            assert thing.counter == 2 

def test_old_tornado(self):
        old_attr = gen.is_coroutine_function
        try:
            del gen.is_coroutine_function

            # is_coroutine_function was introduced in tornado 4.5;
            # verify that we don't *completely* fall over on old versions
            @retry
            def retryable(thing):
                pass
        finally:
            gen.is_coroutine_function = old_attr 

def is_tornado_coroutine(func):
  """
  Return whether *func* is a Tornado coroutine function.
  Running coroutines are not supported.
  """
  if 'tornado.gen' not in sys.modules:
    return False
  gen = sys.modules['tornado.gen']
  if not hasattr(gen, "is_coroutine_function"):
    # Tornado version is too old
    return False
  return gen.is_coroutine_function(func) 

def test_is_coroutine_function(self):
        self.finished = True

        def f():
            yield gen.moment

        coro = gen.coroutine(f)
        self.assertFalse(gen.is_coroutine_function(f))
        self.assertTrue(gen.is_coroutine_function(coro))
        self.assertFalse(gen.is_coroutine_function(coro()))