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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def newfeed(ctx, symbol, price, market, cer, mssr, mcr, account):
 """ Publish a price feed! Examples: \b uptick newfeed USD 0.01 USD/BTS uptick newfeed USD 100 BTS/USD Core Exchange Rate (CER) \b If no CER is provided, the cer will be the same as the settlement price with a 5% premium (Only if the 'market' is against the core asset (e.g. BTS)). The CER is always defined against the core asset (BTS). This means that if the backing asset is not the core asset (BTS), then you must specify your own cer as a float. The float `x` will be interpreted as `x BTS/SYMBOL`. """

    if cer:
        cer = Price(cer, quote=symbol, base="1.3.0", bitshares_instance=ctx.bitshares)

    print_tx(
        ctx.bitshares.publish_price_feed(
            symbol, Price(price, market), cer=cer, mssr=mssr, mcr=mcr, account=account
        )
    )