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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 __set_lost_start_status(self, hgvs_string):
 """Sets the self.is_lost_start flag."""

        # set is lost start status
        mymatch = re.search('^([A-Z?])(\d+)([A-Z?])$', hgvs_string)
        if mymatch:
            grps = mymatch.groups()
            if int(grps[1]) == 1 and grps[0] != grps[2]:
                self.is_lost_start = True
                self.is_non_silent = True
            else:
                self.is_lost_start = False
        else:
            self.is_lost_start = False