code: func (ec *Client) PendingBalanceAt(ctx context.Context, account common.Address) (*big.Int, error) {
  	var result hexutil.Big
  	err := ec.c.CallContext(ctx, &result, "eth_getBalance", account, "pending")
  	return (*big.Int)(&result), err
  }
docs: // Pending State
  // PendingBalanceAt returns the wei balance of the given account in the pending state.