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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 _call(self, x):
 """Sum all values if indices are given multiple times."""

        y = np.bincount(self._indices_flat, weights=x,
                        minlength=self.range.size)

        out = y.reshape(self.range.shape)

        if self.variant == 'dirac':
            weights = getattr(self.range, 'cell_volume', 1.0)
        elif self.variant == 'char_fun':
            weights = 1.0
        else:
            raise RuntimeError('The variant "{!r}" is not yet supported'
                               ''.format(self.variant))

        if weights != 1.0:
            out /= weights

        return out