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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 open(self, name, *args, **kwargs):
 """Open file, possibly relative to a base directory."""

        if self.basedir is not None:
            name = os.path.join(self.basedir, name)

        return em.Subsystem.open(self, name, *args, **kwargs)