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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 lorentz_deriv((x, y, z), t0, sigma=10., beta=8./3, rho=28.0):
 """Compute the time-derivative of a Lorentz system."""

    return [sigma * (y - x), x * (rho - z) - y, x * y - beta * z]