twisted.internet.error.ReactorAlreadyInstalledError: reactor already installed [5804] Failed to execute script main

C++
import kivy
kivy.require('1.9.1')

# fix for pyinstaller packages app to avoid ReactorAlreadyInstalledError
import sys
if 'twisted.internet.reactor' in sys.modules:
    del sys.modules['twisted.internet.reactor']

# install twisted reactor
from kivy.support import install_twisted_reactor
install_twisted_reactor()

Source

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