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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_env(self, config):
 """ Read environment variables based on the settings defined in the defaults. These are expected to be upper-case versions of the actual setting names, prefixed by ``SCRAPEKIT_``. """

        for option, value in config.items():
            env_name = 'SCRAPEKIT_%s' % option.upper()
            value = os.environ.get(env_name, value)
            config[option] = value
        return config