[python-sdk] Add a simple bcs serializer / deserializer
[python-sdk] Add a simple bcs serializer / deserializer

aptos-labs/aptos-core,aptos-labs/aptos-core,aptos-labs/aptos-core,aptos-labs/aptos-core,aptos-labs/aptos-core,aptos-labs/aptos-core,aptos-labs/aptos-core