hi, ive got these two functions: @inlineCallbacks def getUserList(): reload_interval = yield getReloadInterval() print "222", reload_interval target_url = host + "/?ReloaderUserOnline" body = urllib.urlencode({"reloadsequenz":reload_interval}) #body = '\r\n' #headers = {'Content-Type': 'application/x-www-form-urlencoded'} d = getPage(url = target_url, cookies=cookies, agent=useragent, postdata=body, method = 'POST', headers=headers) defer.returnValue(d) i can see the output: 222 somenumber, so apparently getReloadInterval works. it returns some magic number as expected now i call getUserList from this function: (response is 1, so d = getUserList gets evaluated) but there i get: 222 5821 Unhandled error in Deferred (short version, complete error at the end) Traceback (most recent call last): File "/home/julius/.local/lib/python2.7/site-packages/twisted/internet/defer.py", line 1184, in gotResult def printLoginResult(response): #we are in, login accepted if response == ' 1': print "we are in, get user list" #printChat(response) def printResult(result): print repr(result) d = getUserList() d.addCallback(printResult) d.addErrback(printResult) why is printResult not run? Unhandled error in Deferred: Traceback (most recent call last): File "/home/julius/.local/lib/python2.7/site-packages/twisted/internet/defer.py", line 1184, in gotResult _inlineCallbacks(r, g, deferred) File "/home/julius/.local/lib/python2.7/site-packages/twisted/internet/defer.py", line 1171, in _inlineCallbacks deferred.callback(e.value) File "/home/julius/.local/lib/python2.7/site-packages/twisted/internet/defer.py", line 393, in callback self._startRunCallbacks(result) File "/home/julius/.local/lib/python2.7/site-packages/twisted/internet/defer.py", line 501, in _startRunCallbacks self._runCallbacks() --- <exception caught here> --- File "/home/julius/.local/lib/python2.7/site-packages/twisted/internet/defer.py", line 588, in _runCallbacks current.result = callback(current.result, *args, **kw) File "/home/julius/.local/lib/python2.7/site-packages/twisted/internet/defer.py", line 1184, in gotResult _inlineCallbacks(r, g, deferred) File "/home/julius/.local/lib/python2.7/site-packages/twisted/internet/defer.py", line 1171, in _inlineCallbacks deferred.callback(e.value) File "/home/julius/.local/lib/python2.7/site-packages/twisted/internet/defer.py", line 392, in callback assert not isinstance(result, Deferred) exceptions.AssertionError: