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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 delete(self, data_src):
 """ Delete data sources. """

        items = self.objects[data_src].data.keys()  # items to edit
        self.reg.unregister(items)  # remove items from Registry
        self.layer.pop(data_src)  # remove data source from layer
        self.objects.pop(data_src)  # remove data_source object
        self.sources.pop(data_src)