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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):
 """Return a TarInfo object for member `name'. If `name' can not be found in the archive, KeyError is raised. If a member occurs more than once in the archive, its last occurrence is assumed to be the most up-to-date version. """

        tarinfo = self._getmember(name)
        if tarinfo is None:
            raise KeyError("filename %r not found" % name)
        return tarinfo