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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 go_aspect(self, go_term):
 """ For GO terms, returns F, C, or P corresponding to its aspect """

        if not go_term.startswith("GO:"):
            return None
        else:
            # Check ancestors for root terms
            if self.is_molecular_function(go_term):
                return 'F'
            elif self.is_cellular_component(go_term):
                return 'C'
            elif self.is_biological_process(go_term):
                return 'P'