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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 sideral(date, longitude=0., model='mean', eop_correction=True, terms=106):
 # pragma: no cover """Sideral time as a rotation matrix """

    theta = _sideral(date, longitude, model, eop_correction, terms)
    return rot3(np.deg2rad(-theta))