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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 _apply(self, f, grouper=None, *args, **kwargs):
 """ Dispatch to _upsample; we are stripping all of the _upsample kwargs and performing the original function call on the grouped object. """


        def func(x):
            x = self._shallow_copy(x, groupby=self.groupby)

            if isinstance(f, str):
                return getattr(x, f)(**kwargs)

            return x.apply(f, *args, **kwargs)

        result = self._groupby.apply(func)
        return self._wrap_result(result)