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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 create_bitcoind_service_proxy( rpc_username, rpc_password, server='127.0.0.1', port=8332, use_https=False):
 """ create a bitcoind service proxy """

    protocol = 'https' if use_https else 'http'
    uri = '%s://%s:%s@%s:%s' % (protocol, rpc_username, rpc_password,
        server, port)
    return AuthServiceProxy(uri)