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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 swap_dims(self, dims_dict, inplace=None):
 """Returns a new object with swapped dimensions. Parameters dims_dict : dict-like Dictionary whose keys are current dimension names and whose values are new names. Each value must already be a variable in the dataset. inplace : bool, optional If True, swap dimensions in-place. Otherwise, return a new dataset object. Returns ------- renamed : Dataset Dataset with swapped dimensions. See Also -------- Dataset.rename DataArray.swap_dims """

        # TODO: deprecate this method in favor of a (less confusing)
        # rename_dims() method that only renames dimensions.
        inplace = _check_inplace(inplace)
        for k, v in dims_dict.items():
            if k not in self.dims:
                raise ValueError('cannot swap from dimension %r because it is '
                                 'not an existing dimension' % k)
            if self.variables[v].dims != (k,):
                raise ValueError('replacement dimension %r is not a 1D '
                                 'variable along the old dimension %r'
                                 % (v, k))

        result_dims = set(dims_dict.get(dim, dim) for dim in self.dims)

        coord_names = self._coord_names.copy()
        coord_names.update(dims_dict.values())

        variables = OrderedDict()
        indexes = OrderedDict()
        for k, v in self.variables.items():
            dims = tuple(dims_dict.get(dim, dim) for dim in v.dims)
            if k in result_dims:
                var = v.to_index_variable()
                if k in self.indexes:
                    indexes[k] = self.indexes[k]
                else:
                    indexes[k] = var.to_index()
            else:
                var = v.to_base_variable()
            var.dims = dims
            variables[k] = var

        return self._replace_with_new_dims(variables, coord_names,
                                           indexes=indexes, inplace=inplace)