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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 set_sources(self, sources):
 """ Creates GeocodeServiceConfigs from each str source """

        if len(sources) == 0:
            raise Exception('Must declare at least one source for a geocoder')
        self._sources = []
        for source in sources:  # iterate through a list of sources
            self.add_source(source)