[Twisted-Python] qt5 / twisted integration....reactor imported but NameError?

[steven meier]

python main_code.py 
Gtk-Message: Failed to load module "canberra-gtk-module"
testing...
[Failure instance: Traceback: <type 'exceptions.NameError'>: global name
'reactor' is not defined
/home/julius/.local/lib/python2.7/site-packages/twisted/internet/tcp.py:293:connectionLost
/home/julius/.local/lib/python2.7/site-packages/twisted/web/client.py:222:connectionLost
/home/julius/.local/lib/python2.7/site-packages/twisted/internet/defer.py:393:callback
/home/julius/.local/lib/python2.7/site-packages/twisted/internet/defer.py:501:_startRunCallbacks
--- <exception caught here> ---
/home/julius/.local/lib/python2.7/site-packages/twisted/internet/defer.py:588:_runCallbacks
/home/julius/code/python/qt5-python2.x/webchat.py:75:main_page_result
]
123



main_code looks like this:
from PyQt5 import QtWidgets
import sys
from untitled import Ui_MainWindow




class Main(QtWidgets.QMainWindow):

    def __init__(self):
        QtWidgets.QMainWindow.__init__(self)
        self.ui = Ui_MainWindow()
        self.ui.setupUi(self)
        self.setupSignals()

    def button_1_Clicked(self):
        self.ui.textbox_2.setText(self.ui.textbox_1.text())

    def setupSignals(self):
        #self.ui.textbox_1.textChanged.connect(self.textbox_1_Changed)
        self.ui.button_1.clicked.connect(self.button_1_Clicked)



if __name__ == '__main__':
    #app = QtWidgets.QApplication(sys.argv)
    app = QtWidgets.QApplication(sys.argv) # your code to init QtCore
    import qt5reactor
    qt5reactor.install()
    from twisted.internet import reactor
    print "testing..."

<snip>

    from webchat import get_main_page
    get_main_page()
    reactor.run()




as you can see the qt5reactor.install() runs before the "from webchat
import get_main_page"

so how come that webchat does not know about reactor?