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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 add_redirect_uris(request_args, service=None, **kwargs):
 """ Add redirect_uris to the request arguments. :param request_args: Incomming request arguments :param service: A link to the service :param kwargs: Possible extra keyword arguments :return: A possibly augmented set of request arguments. """

    _context = service.service_context
    if "redirect_uris" not in request_args:
        # Callbacks is a dictionary with callback type 'code', 'implicit',
        # 'form_post' as keys.
        try:
            _cbs = _context.callbacks
        except AttributeError:
            request_args['redirect_uris'] = _context.redirect_uris
        else:
            # Filter out local additions.
            _uris = [v for k, v in _cbs.items() if not k.startswith('__')]
            request_args['redirect_uris'] = _uris

    return request_args, {}