code: func (ec *Client) PendingTransactionCount(ctx context.Context) (uint, error) {
  	var num hexutil.Uint
  	err := ec.c.CallContext(ctx, &num, "eth_getBlockTransactionCountByNumber", "pending")
  	return uint(num), err
  }
docs: // PendingTransactionCount returns the total number of transactions in the pending state.