def installReactor(shortName):
    """
    Install the reactor with the given C{shortName} attribute.

    @raise NoSuchReactor: If no reactor is found with a matching C{shortName}.

    @raise: anything that the specified reactor can raise when installed.
    """
    for installer in getReactorTypes():
        if installer.shortName == shortName:
            installer.install()
            from twisted.internet import reactor
            return reactor
    raise NoSuchReactor(shortName)

    Install the reactor with the given C{shortName} attribute.

    @raise NoSuchReactor: If no reactor is found with a matching C{shortName}.

    @raise: anything that the specified reactor can raise when installed.
    
stackoverflow/venv/lib/python3.6/site-packages/twisted/application/reactors.py