Duplicate identifier 'alpha'.deno-ts(2300) Unexpected keyword or identifier

Question

I am trying to use Alpha Vantage NPM package inside my Deno application. I tried to use SkyPack version of it. But it gives me the following error:

Duplicate identifier 'alpha'.deno-ts(2300)
Unexpected keyword or identifier.

This is the code I am using:

import alphavantageTs from 'https://cdn.skypack.dev/alphavantage-ts';

export class StockTimeSeries{
        alpha = new alphavantageTs ("ASLDVIWXGEWFWNZG");

        alpha.stocks.intraday("msft").then((data: any) => {
            console.log(data);
            });
        
        alpha.stocks.batch(["msft", "aapl"]).then((data: any) => {
        console.log(data);
        });
    
        alpha.forex.rate("btc", "usd").then((data: any) => {
        console.log(data);
        });
    
        alpha.crypto.intraday("btc", "usd").then((data: any) => {
        console.log(data);
        });
    
        alpha.technicals.sma("msft", "daily", 60, "close").then((data: any) => {
        console.log(data);
        });
    
        alpha.sectors.performance().then((data: any) => {
        console.log(data);
        });
   

}