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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 get_path(self, obj, default):
 """Return a relative or absolute path to experimental data."""

        path = obj.get("path")
        if path is None:
            path = join(self._base, default)
        if not isabs(path):
            path = join(self._base, path)
        return path