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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 sort_values(self, by=None, axis=0, ascending=True, inplace=False, kind='quicksort', na_position='last'):
 """ Sort by the values along either axis. Parameters axis : %(axes_single_arg)s, default 0 Axis to be sorted. ascending : bool or list of bool, default True Sort ascending vs. descending. Specify list for multiple sort orders. If this is a list of bools, must match the length of the by. inplace : bool, default False If True, perform operation in-place. kind : {'quicksort', 'mergesort', 'heapsort'}, default 'quicksort' Choice of sorting algorithm. See also ndarray.np.sort for more information. `mergesort` is the only stable algorithm. For DataFrames, this option is only applied when sorting on a single column or label. na_position : {'first', 'last'}, default 'last' Puts NaNs at the beginning if `first`; `last` puts NaNs at the end. Returns ------- sorted_obj : DataFrame or None DataFrame with sorted values if inplace=False, None otherwise. Examples -------- col1 col2 col3 0 A 2 0 1 A 1 1 2 B 9 9 3 NaN 8 4 4 D 7 2 5 C 4 3 Sort by col1 col1 col2 col3 0 A 2 0 1 A 1 1 2 B 9 9 5 C 4 3 4 D 7 2 3 NaN 8 4 Sort by multiple columns col1 col2 col3 1 A 1 1 0 A 2 0 2 B 9 9 5 C 4 3 4 D 7 2 3 NaN 8 4 Sort Descending col1 col2 col3 4 D 7 2 5 C 4 3 2 B 9 9 0 A 2 0 1 A 1 1 3 NaN 8 4 Putting NAs first col1 col2 col3 3 NaN 8 4 4 D 7 2 5 C 4 3 2 B 9 9 0 A 2 0 1 A 1 1 """

        raise NotImplementedError("sort_values has not been implemented "
                                  "on Panel or Panel4D objects.")