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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 best_identities(self):
 """Returns identities of the best HSP in alignment. """

        if len(self.hsp_list) > 0:
            return round(float(self.hsp_list[0].identities) / float(self.hsp_list[0].align_length) * 100, 1)