Returns a list of pairs of account and block hash representing the
        head block starting at **account** up to **count**

        :param account: Account to get frontier blocks for
        :type account: str

        :param count: Max amount to return
        :type count: int

        :raises: :py:exc:`nano.rpc.RPCException`

        >>> rpc.frontiers(
        ...     account="xrb_1111111111111111111111111111111111111111111111111111hifc8npp",
        ...     count=1
        ... )
        {
            "xrb_3e3j5tkog48pnny9dmfzj1r16pg8t1e76dz5tmac6iq689wyjfpi00000000":
                "000D1BAEC8EC208142C99059B393051BAC8380F9B5A2E6B2489A277D81789F3F"
        }

def frontiers(self, account, count):
        """
        Returns a list of pairs of account and block hash representing the
        head block starting at **account** up to **count**

        :param account: Account to get frontier blocks for
        :type account: str

        :param count: Max amount to return
        :type count: int

        :raises: :py:exc:`nano.rpc.RPCException`

        >>> rpc.frontiers(
        ...     account="xrb_1111111111111111111111111111111111111111111111111111hifc8npp",
        ...     count=1
        ... )
        {
            "xrb_3e3j5tkog48pnny9dmfzj1r16pg8t1e76dz5tmac6iq689wyjfpi00000000":
                "000D1BAEC8EC208142C99059B393051BAC8380F9B5A2E6B2489A277D81789F3F"
        }

        """

        account = self._process_value(account, 'account')
        count = self._process_value(count, 'int')

        payload = {"account": account, "count": count}

        resp = self.call('frontiers', payload)

        return resp.get('frontiers') or {}