se     (bool, optional, default=false) If false, return a string, otherwise return a json object
3. "blockhash" (string, optional) The block in which to look for the transaction

Result (if verbose is not set or set to false):
"data"      (string) The serialized, hex-encoded data for 'txid'

Result (if verbose is set to true):
{
  "in_active_chain": b, (bool) Whether specified block is in the active chain or not (only present with explicit "blockhash" argument)
  "hex" : "data",       (string) The serialize