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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 equation_of_time_pvcdrom(dayofyear):
 """ Equation of time from PVCDROM. `PVCDROM`_ is a website by Solar Power Lab at Arizona State University (ASU) .. _PVCDROM: http://www.pveducation.org/pvcdrom/2-properties-sunlight/solar-time Parameters dayofyear : numeric Returns ------- equation_of_time : numeric Difference in time between solar time and mean solar time in minutes. References [1] Soteris A. Kalogirou, "Solar Energy Engineering Processes and Systems, 2nd Edition" Elselvier/Academic Press (2009). See Also -------- equation_of_time_Spencer71 """

    # day angle relative to Vernal Equinox, typically March 22 (day number 81)
    bday = \
        _calculate_simple_day_angle(dayofyear) - (2.0 * np.pi / 365.0) * 80.0
    # same value but about 2x faster than Spencer (1971)
    return 9.87 * np.sin(2.0 * bday) - 7.53 * np.cos(bday) - 1.5 * np.sin(bday)