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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 _unique_name(name, seen):
 """Append incremental '.N' suffix if glyph is a duplicate."""

        if name in seen:
            n = seen[name]
            while (name + ".%d" % n) in seen:
                n += 1
            seen[name] = n + 1
            name += ".%d" % n
        seen[name] = 1
        return name