code: def namedb_account_transaction_save(cur, address, token_type, new_credit_value, new_debit_value, block_id, vtxindex, txid, existing_account):
      
      if existing_account is None:
          existing_account = {}
  
      accounts_insert = {
          'address': address,
          'type': token_type,
          'credit_value': '{}'.format(new_credit_value),
          'debit_value': '{}'.format(new_debit_value),
          'lock_transfer_block_id': existing_account.get('lock_transfer_block_id', 0),        # unlocks immediately if the account doesn't exist
          'receive_whitelisted': existing_account.get('receive_whitelisted', True),           # new accounts are whitelisted by default (for now)
          'metadata': existing_account.get('metadata', None),
          'block_id': block_id,
          'txid': txid,
          'vtxindex': vtxindex
      }
  
      try:
          query, values = namedb_insert_prepare(cur, accounts_insert, 'accounts')
      except Exception as e:
          log.exception(e)
          log.fatal('FATAL: failed to append account history record for {} at ({},{})'.format(address, block_id, vtxindex))
          os.abort()
      
      namedb_query_execute(cur, query, values)
      return True
docs: Insert the new state of an account at a particular point in time.
  
      The data must be for a never-before-seen (txid,block_id,vtxindex) set in the accounts table, but must
      correspond to an entry in the history table.
  
      If existing_account is not None, then copy all other remaining fields from it.
  
      Return True on success
      Raise an Exception on error