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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 _getmember(self, name, tarinfo=None, normalize=False):
 """Find an archive member by name from bottom to top. If tarinfo is given, it is used as the starting point. """

        # Ensure that all members have been loaded.
        members = self.getmembers()

        # Limit the member search list up to tarinfo.
        if tarinfo is not None:
            members = members[:members.index(tarinfo)]

        if normalize:
            name = os.path.normpath(name)

        for member in reversed(members):
            if normalize:
                member_name = os.path.normpath(member.name)
            else:
                member_name = member.name

            if name == member_name:
                return member