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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 resize_dimension(self, dimension, size):
 """ Resize a dimension to a certain size. It will pad with the underlying HDF5 data sets' fill values (usually zero) where necessary. """

        if self.dimensions[dimension] is not None:
            raise ValueError("Dimension '%s' is not unlimited and thus "
                             "cannot be resized." % dimension)

        # Resize the dimension.
        self._current_dim_sizes[dimension] = size

        for var in self.variables.values():
            new_shape = list(var.shape)
            for i, d in enumerate(var.dimensions):
                if d == dimension:
                    new_shape[i] = size
            new_shape = tuple(new_shape)
            if new_shape != var.shape:
                var._h5ds.resize(new_shape)

        # Recurse as dimensions are visible to this group and all child groups.
        for i in self.groups.values():
            i.resize_dimension(dimension, size)