,             (numeric) The median block time expressed in UNIX epoch time
  "nonce" : n,                    (numeric) The nonce
  "bits" : "hex",                 (string) The bits
  "difficulty" : n,               (numeric) The difficulty
  "chainwork" : "hex",            (string) Expected number of hashes required to produce the chain up to this block (in hex)
  "nTx" : n,                      (numeric) The number of transactions in the block
  "previousblockhash" : "hex",    (string, optional) The hash o