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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 nexrad_to_datetime(julian_date, ms_midnight):
 """Convert NEXRAD date time format to python `datetime.datetime`."""

    # Subtracting one from julian_date is because epoch date is 1
    return datetime.datetime.utcfromtimestamp((julian_date - 1) * day + ms_midnight * milli)