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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 _calc_sampleset(w1, w2, step, minimal):
 """Calculate sampleset for each model."""

        if minimal:
            arr = [w1 - step, w1, w2, w2 + step]
        else:
            arr = np.arange(w1 - step, w2 + step + step, step)

        return arr