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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):
 """Get the sideral time at a defined date Args: date (Date):
 longitude (float):
 Longitude of the observer (in degrees) East positive/West negative. model (str):
 'mean' or 'apparent' for GMST and GAST respectively Return: float: Sideral time in degrees GMST: Greenwich Mean Sideral Time LST: Local Sideral Time (Mean) GAST: Greenwich Apparent Sideral Time """


    t = date.change_scale('UT1').julian_century

    # Compute GMST in seconds
    theta = 67310.54841 + (876600 * 3600 + 8640184.812866) * t + 0.093104 * t ** 2\
        - 6.2e-6 * t ** 3

    # Conversion from second (time) to degrees (angle)
    theta /= 240.

    if model == 'apparent':
        theta += equinox(date, eop_correction, terms)

    # Add local longitude to the sideral time
    theta += longitude
    # Force to 0-360 degrees range
    theta %= 360.

    return theta