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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 variant_indices(self):
 """ When we combine prefix + alt + suffix into a single string, what are is base-0 index interval which gets us back the alt sequence? First returned index is inclusive, the second is exclusive. """

        variant_start_index = len(self.prefix)
        variant_len = len(self.alt)
        variant_end_index = variant_start_index + variant_len
        return variant_start_index, variant_end_index