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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 sparse_counts_map(self):
 """ return a counts map with sparse index scheme """

        if self.hpx._ipix is None:
            flatarray = self.data.flattern()
        else:
            flatarray = self.expanded_counts_map()
        nz = flatarray.nonzero()[0]
        data_out = flatarray[nz]
        return (nz, data_out)