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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def fetcher(ctx, xmlrpc, xmlrpc_host, xmlrpc_port, poolsize, proxy, user_agent, timeout, phantomjs_endpoint, puppeteer_endpoint, splash_endpoint, fetcher_cls, async_mode=True, get_object=False, no_input=False):
 """ Run Fetcher. """

    g = ctx.obj
    Fetcher = load_cls(None, None, fetcher_cls)

    if no_input:
        inqueue = None
        outqueue = None
    else:
        inqueue = g.scheduler2fetcher
        outqueue = g.fetcher2processor
    fetcher = Fetcher(inqueue=inqueue, outqueue=outqueue,
                      poolsize=poolsize, proxy=proxy, async_mode=async_mode)
    fetcher.phantomjs_proxy = phantomjs_endpoint or g.phantomjs_proxy
    fetcher.puppeteer_proxy = puppeteer_endpoint or g.puppeteer_proxy
    fetcher.splash_endpoint = splash_endpoint
    if user_agent:
        fetcher.user_agent = user_agent
    if timeout:
        fetcher.default_options = copy.deepcopy(fetcher.default_options)
        fetcher.default_options['timeout'] = timeout

    g.instances.append(fetcher)
    if g.get('testing_mode') or get_object:
        return fetcher

    if xmlrpc:
        utils.run_in_thread(fetcher.xmlrpc_run, port=xmlrpc_port, bind=xmlrpc_host)
    fetcher.run()