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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 get_tickers_from_file(self, filename):
 """Load ticker list from txt file"""

        if not os.path.exists(filename):
            log.error("Ticker List file does not exist: %s", filename)

        tickers = []
        with io.open(filename, 'r') as fd:
            for ticker in fd:
                tickers.append(ticker.rstrip())
        return tickers