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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 save_docstring(self, key):
 """ Descriptor method to save a docstring from a function Like the :meth:`get_sectionsf` method this method serves as a descriptor for functions but saves the entire docstring"""

        def func(f):
            self.params[key] = f.__doc__ or ''
            return f
        return func