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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 now(utc=False, tz=None):
 """ Get a current DateTime object. By default is local. .. code:: python reusables.now() # DateTime(2016, 12, 8, 22, 5, 2, 517000) reusables.now().format("It's {24-hour}:{min}") # "It's 22:05" :param utc: bool, default False, UTC time not local :param tz: TimeZone as specified by the datetime module :return: reusables.DateTime """

    return datetime.datetime.utcnow() if utc else datetime.datetime.now(tz=tz)