date_range() : allowing argument closed to have value 'open'
#### Code Sample

```
# My current code to get rid of both extremities of the DateTimeIndex  returned by date_range()
def my_date_range(start: pd.Timestamp, end: pd.Timestamp, freq: str) -> pd.DatetimeIndex:
    """
    Remove automatically first and last timestamps from the generated DateTimeIndex.
    """

    DTI = pd.date_range(start = start, end = end, freq = freq, closed = 'left')

    # Last timestamp has not been kept with use of 'closed' keyword, 'left' value.
    # With delete, the 1st timestamp is also removed.
    return DTI.delete(0)

# Now, I can use date_range() the way I want with apply() function :)
time_range = df.apply(lambda x: pd.Series(my_date_range(x.name, x.End, x.Freq)), axis=1).stack()

```
#### Problem description

Please, could the keyword 'closed' accept a 4th value (for instance 'open') that allows suppressing both extremities of the DateTimeIndex?

Thanks for your help and this marvelous library! Loving it!
;)

