def _get_address_by_hash(self, block_hash):
        """Get mapped address by its hash.

        :param block_hash:
        :return:
        """
        address_key = address_prefix + block_hash
        return self.db.get(address_key)
def _get_address_by_hash ( self , block_hash ) : address_key = address_prefix + block_hash return self . db . get ( address_key )
Get mapped address by its hash.

        :param block_hash:
        :return: