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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 argmin(self, axis=None, skipna=True):
 """ Return a ndarray of the minimum argument indexer. Parameters axis : {None} Dummy argument for consistency with Series skipna : bool, default True Returns ------- numpy.ndarray See Also -------- numpy.ndarray.argmin """

        nv.validate_minmax_axis(axis)
        return nanops.nanargmin(self._values, skipna=skipna)