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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 complete_timeframe(timeframe, config, partial=False):
 """ Apply fallback strategy to incomplete timeframes. Our fallback strategy is as follows: * Missing start-date: Fallback to ``today``. * Missing start-time: Fallback to ``store.config['day_start']``. * Missing end-date: Fallback to ``today`` for ``day_start='00:00`, ``tomorrow`` otherwise. See ``hamster_lib.helpers.end_day_to_datetime`` for details and explanations. * Missing end-time: 1 second before ``store.config['day_start']``. Args: timeframe (TimeFrame):
 ``TimeFrame`` instance incorporating all available information available about the timespan. Any missing info will be completed per fallback strategy. config (dict):
 A config-dict providing settings relevant to determine fallback values. partial (bool, optional):
 If true, we will only complete start/end times if there is at least either date or time information present. Defaults to ``False``. Returns: tuple: ``(start, end)`` tuple. Where ``start`` and ``end`` are full ``datetime.datetime`` instances. Raises: TypeError: If any of the ``timeframe`` values is of inappropriate datetime type. """


    def complete_start_date(date):
        """
        Assign ``today`` if ``date=None``, else ensure its a ``datetime.date`` instance.

        Args:
            date (datetime.date): Startdate information.

        Returns:
            datetime.date: Either the original date or the default solution.

        Raises:
            TypeError: If ``date``` is neither ``None`` nor  ``datetime.date`` instance.

        Note:
            Reference behavior taken from [hamster-cli](https://github.com/projecthamster/
            hamster/blob/master/src/hamster-cli#L368).
        """

        if not date:
            date = datetime.date.today()
        else:
            if not isinstance(date, datetime.date):
                raise TypeError(_(
                    "Expected datetime.date instance, got {type} instead.".format(
                        type=type(date))
                ))
        return date

    def complete_start_time(time, day_start):
        """Assign ``day_start`` if no start-time is given."""
        if not time:
            time = day_start
        else:
            if not isinstance(time, datetime.time):
                raise TypeError(_(
                    "Expected datetime.time instance, got {type} instead.".format(
                        type=type(time))
                ))
        return time

    def complete_start(date, time, config):
        return datetime.datetime.combine(
            complete_start_date(timeframe.start_date),
            complete_start_time(timeframe.start_time, config['day_start']),
        )

    def complete_end_date(date):
        if not date:
            date = datetime.date.today()
        else:
            if not isinstance(date, datetime.date):
                raise TypeError(_(
                    "Expected datetime.date instance, got {type} instead.".format(
                        type=type(date))
                ))
        return date

    def complete_end(date, time, config):
        date = complete_end_date(date)
        if time:
            result = datetime.datetime.combine(date, time)
        else:
            result = end_day_to_datetime(date, config)
        return result

    start, end = None, None

    if any((timeframe.offset, timeframe.start_time, timeframe.start_date)) or not partial:
        if not timeframe.offset:
            start = complete_start(timeframe.start_date, timeframe.start_time, config)
        else:
            start = datetime.datetime.now() - timeframe.offset

    if any((timeframe.end_date, timeframe.end_time)) or not partial:
        end = complete_end(timeframe.end_date, timeframe.end_time, config)

    return (start, end)