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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 rename(self, name_dict=None, inplace=None, **names):
 """Returns a new object with renamed variables and dimensions. Parameters name_dict : dict-like, optional Dictionary whose keys are current variable or dimension names and whose values are the desired names. inplace : bool, optional If True, rename variables and dimensions in-place. Otherwise, return a new dataset object. **names, optional Keyword form of ``name_dict``. One of name_dict or names must be provided. Returns ------- renamed : Dataset Dataset with renamed variables and dimensions. See Also -------- Dataset.swap_dims DataArray.rename """

        # TODO: add separate rename_vars and rename_dims methods.
        inplace = _check_inplace(inplace)
        name_dict = either_dict_or_kwargs(name_dict, names, 'rename')
        for k, v in name_dict.items():
            if k not in self and k not in self.dims:
                raise ValueError("cannot rename %r because it is not a "
                                 "variable or dimension in this dataset" % k)

        variables, coord_names, dims, indexes = self._rename_all(
            name_dict=name_dict, dim_dict=name_dict)
        return self._replace(variables, coord_names, dims=dims,
                             indexes=indexes, inplace=inplace)