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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_emissions(self, scenario):
 """Set emissions from Pandas DataFrame."""

        for section in emissions:
            for source in emissions[section]:
                if source not in scenario.columns:
                    continue
                self._set_timed_array(
                    section, source, list(scenario.index), list(scenario[source])
                )