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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 cf_decoder(variables, attributes, concat_characters=True, mask_and_scale=True, decode_times=True):
 """ Decode a set of CF encoded variables and attributes. See Also, decode_cf_variable Parameters variables : dict A dictionary mapping from variable name to xarray.Variable attributes : dict A dictionary mapping from attribute name to value concat_characters : bool Should character arrays be concatenated to strings, for example: ['h', 'e', 'l', 'l', 'o'] -> 'hello' mask_and_scale: bool Lazily scale (using scale_factor and add_offset) and mask (using _FillValue). decode_times : bool Decode cf times ('hours since 2000-01-01') to np.datetime64. Returns ------- decoded_variables : dict A dictionary mapping from variable name to xarray.Variable objects. decoded_attributes : dict A dictionary mapping from attribute name to values. """

    variables, attributes, _ = decode_cf_variables(
        variables, attributes, concat_characters, mask_and_scale, decode_times)
    return variables, attributes