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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 astimezone_and_leap_second(self, tz):
 """Convert to a Python ``datetime`` and leap second in a timezone. Convert this time to a Python ``datetime`` and a leap second:: dt, leap_second = t.astimezone_and_leap_second(tz) The argument ``tz`` should be a timezone from the third-party ``pytz`` package, which must be installed separately. The date and time returned will be for that time zone. The leap second value is provided because a Python ``datetime`` can only number seconds ``0`` through ``59``, but leap seconds have a designation of at least ``60``. The leap second return value will normally be ``0``, but will instead be ``1`` if the date and time are a UTC leap second. Add the leap second value to the ``second`` field of the ``datetime`` to learn the real name of the second. If this time is an array, then an array of ``datetime`` objects and an array of leap second integers is returned, instead of a single value each. """

        dt, leap_second = self.utc_datetime_and_leap_second()
        normalize = getattr(tz, 'normalize', None)
        if self.shape and normalize is not None:
            dt = array([normalize(d.astimezone(tz)) for d in dt])
        elif self.shape:
            dt = array([d.astimezone(tz) for d in dt])
        elif normalize is not None:
            dt = normalize(dt.astimezone(tz))
        else:
            dt = dt.astimezone(tz)
        return dt, leap_second