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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 argmax(self, axis=None, skipna=True, *args, **kwargs):
 """ Returns the indices of the maximum values along an axis. See `numpy.ndarray.argmax` for more information on the `axis` parameter. See Also -------- numpy.ndarray.argmax """

        nv.validate_argmax(args, kwargs)
        nv.validate_minmax_axis(axis)

        i8 = self.asi8
        if self.hasnans:
            mask = self._isnan
            if mask.all() or not skipna:
                return -1
            i8 = i8.copy()
            i8[mask] = 0
        return i8.argmax()