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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 load_sources(self, sources):
 """Delete all sources in the ROI and load the input source list."""


        self.clear()
        for s in sources:

            if isinstance(s, dict):
                s = Model.create_from_dict(s)

            self.load_source(s, build_index=False)
        self._build_src_index()