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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 djd_to_datetime(djd, tz='UTC'):
 """ Converts a Dublin Julian Day float to a datetime.datetime object Parameters djd : float fractional days since 12/31/1899+0000 tz : str, default 'UTC' timezone to localize the result to Returns ------- datetime.datetime The resultant datetime localized to tz """


    djd_start = pytz.utc.localize(dt.datetime(1899, 12, 31, 12))

    utc_time = djd_start + dt.timedelta(days=djd)
    return utc_time.astimezone(pytz.timezone(tz))