def sumOutputSerializeSizes(outputs):
    """
    sumOutputSerializeSizes sums up the serialized size of the supplied outputs.

    Args:
        outputs list(TxOut): Transaction outputs.

    Returns:
        int: Estimated size of the byte-encoded transaction outputs.
    """
    serializeSize = 0
    for txOut in outputs:
        serializeSize += txOut.serializeSize()
    return serializeSize
