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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 _attach_dim_scales(self):
 """Attach dimension scales to all variables."""

        for name, var in self.variables.items():
            if name not in self.dimensions:
                for n, dim in enumerate(var.dimensions):
                    var._h5ds.dims[n].attach_scale(self._all_h5groups[dim])

        for subgroup in self.groups.values():
            subgroup._attach_dim_scales()