Transactions and blocks are identified by hashes of their binary contents. In practice these hashes are typically presented as hex-encoded big-endian 256-bit integers which we call IDs. Transaction ID and Block ID are computed by reversing the bytes of the original binary hash and then encoding it in hex.
Most of the time, each object that exposes a binary hash attribute, also exposes a corresponding id attribute.
However, if you need to manually convert a hash to id or the other way around, use the following methods on the BTC object.
Returns a binary hash string for a given hex string.
Returns a hex-encoded identifier for a given binary hash string.