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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):
 """ Get the index of the minimum numeric value in SArray. Returns None on an empty SArray. Raises an exception if called on an SArray with non-numeric type. Returns ------- out : int index of the minimum value of SArray See Also -------- argmax Examples -------- """

        from .sframe import SFrame as _SFrame

        if len(self) == 0:
            return None
        if not any([isinstance(self[0], i) for i in [int,float,long]]):
            raise TypeError("SArray must be of type 'int', 'long', or 'float'.")

        sf = _SFrame(self).add_row_number()
        sf_out = sf.groupby(key_column_names=[],operations={'minimum_x1': _aggregate.ARGMIN('X1','id')})
        return sf_out['minimum_x1'][0]