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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 dt2decyear(dt):
 """Convert datetime to decimal year """

    year = dt.year
    startOfThisYear = datetime(year=year, month=1, day=1)
    startOfNextYear = datetime(year=year+1, month=1, day=1)
    yearElapsed = sinceEpoch(dt) - sinceEpoch(startOfThisYear)
    yearDuration = sinceEpoch(startOfNextYear) - sinceEpoch(startOfThisYear)
    fraction = yearElapsed/yearDuration
    return year + fraction