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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 _utc_to_local(self, data, local_zone="America/Los_Angeles"):
 """ Adjust index of dataframe according to timezone that is requested by user. Parameters data : pd.DataFrame() Pandas dataframe of json timeseries response from server. local_zone : str pytz.timezone string of specified local timezone to change index to. Returns ------- pd.DataFrame() Pandas dataframe with timestamp index adjusted for local timezone. """


        # Accounts for localtime shift
        data.index = data.index.tz_localize(pytz.utc).tz_convert(local_zone)
        
        # Gets rid of extra offset information so can compare with csv data
        data.index = data.index.tz_localize(None)

        return data