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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 top_priority_effect_per_gene_id(self):
 """Highest priority effect for each unique gene ID"""

        return OrderedDict(
            (gene_id, top_priority_effect(variant_effects))
            for (gene_id, variant_effects)
            in self.groupby_gene_id().items())