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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 timedelta_range(start=None, end=None, periods=None, freq=None, name=None, closed=None):
 """ Return a fixed frequency TimedeltaIndex, with day as the default frequency Parameters start : string or timedelta-like, default None Left bound for generating timedeltas end : string or timedelta-like, default None Right bound for generating timedeltas periods : integer, default None Number of periods to generate freq : string or DateOffset, default 'D' Frequency strings can have multiples, e.g. '5H' name : string, default None Name of the resulting TimedeltaIndex closed : string, default None Make the interval closed with respect to the given frequency to the 'left', 'right', or both sides (None) Returns ------- rng : TimedeltaIndex Notes ----- Of the four parameters ``start``, ``end``, ``periods``, and ``freq``, exactly three must be specified. If ``freq`` is omitted, the resulting ``TimedeltaIndex`` will have ``periods`` linearly spaced elements between ``start`` and ``end`` (closed on both sides). To learn more about the frequency strings, please see `this link <http://pandas.pydata.org/pandas-docs/stable/timeseries.html#offset-aliases>`__. Examples -------- TimedeltaIndex(['1 days', '2 days', '3 days', '4 days'], dtype='timedelta64[ns]', freq='D') The ``closed`` parameter specifies which endpoint is included. The default behavior is to include both endpoints. TimedeltaIndex(['2 days', '3 days', '4 days'], dtype='timedelta64[ns]', freq='D') The ``freq`` parameter specifies the frequency of the TimedeltaIndex. Only fixed frequencies can be passed, non-fixed frequencies such as 'M' (month end) will raise. TimedeltaIndex(['1 days 00:00:00', '1 days 06:00:00', '1 days 12:00:00', '1 days 18:00:00', '2 days 00:00:00'], dtype='timedelta64[ns]', freq='6H') Specify ``start``, ``end``, and ``periods``; the frequency is generated automatically (linearly spaced). TimedeltaIndex(['1 days 00:00:00', '2 days 08:00:00', '3 days 16:00:00', '5 days 00:00:00'], dtype='timedelta64[ns]', freq=None) """

    if freq is None and com._any_none(periods, start, end):
        freq = 'D'

    freq, freq_infer = dtl.maybe_infer_freq(freq)
    tdarr = TimedeltaArray._generate_range(start, end, periods, freq,
                                           closed=closed)
    return TimedeltaIndex._simple_new(tdarr._data, freq=tdarr.freq, name=name)