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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 calibration(date, satellite):
 """ Return the calibration dictionary. Keyword arguments: satellite -- the name of the satellite. date -- the datetime of an image. """

    counts_shift = CountsShift()
    space_measurement = SpaceMeasurement()
    prelaunch = PreLaunch()
    postlaunch = PostLaunch()
    return {
        'counts_shift': counts_shift.coefficient(satellite),
        'space_measurement': space_measurement.coefficient(satellite),
        'prelaunch': prelaunch.coefficient(satellite),
        'postlaunch': postlaunch.coefficient(date, satellite)
    }