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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 all_same_proj(self):
 """All contained data array are in the same projection."""

        all_areas = [x.attrs.get('area', None) for x in self.values()]
        all_areas = [x for x in all_areas if x is not None]
        return all(all_areas[0].proj_str == x.proj_str for x in all_areas[1:])