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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 dense_output(t_current, t_old, h_current, rcont):
 """ Dense output function, basically extrapolatin """

    # initialization
    s = (t_current - t_old) / h_current
    s1 = 1.0 - s

    return rcont[0] + s * (rcont[1] + s1 * (
            rcont[2] + s * (rcont[3] + s1 * (rcont[4] + s * (rcont[5] + s1 * (rcont[6] + s * rcont[7]))))))