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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 _determine_current_dimension_size(self, dim_name, max_size):
 """ Helper method to determine the current size of a dimension. """

        # Limited dimension.
        if self.dimensions[dim_name] is not None:
            return max_size

        def _find_dim(h5group, dim):
            if dim not in h5group:
                return _find_dim(h5group.parent, dim)
            return h5group[dim]

        dim_variable = _find_dim(self._h5group, dim_name)

        if "REFERENCE_LIST" not in dim_variable.attrs:
            return max_size

        root = self._h5group["/"]

        for ref, _ in dim_variable.attrs["REFERENCE_LIST"]:
            var = root[ref]

            for i, var_d in enumerate(var.dims):
                name = _name_from_dimension(var_d)
                if name == dim_name:
                    max_size = max(var.shape[i], max_size)
        return max_size