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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 _lookup_handler(name):
 """ Look up the implementation of a named handler. Broken out for testing purposes. :param name: The name of the handler to look up. :returns: A factory function for the log handler. """


    # Look up and load the handler factory
    for ep in pkg_resources.iter_entry_points('bark.handler', name):
        try:
            # Load and return the handler factory
            return ep.load()
        except (ImportError, pkg_resources.UnknownExtra):
            # Couldn't load it...
            continue

    raise ImportError("Unknown log file handler %r" % name)