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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 pitching_stats_bref(season=None):
 """ Get all pitching stats for a set season. If no argument is supplied, gives stats for current season to date. """

    if season is None:
        season = datetime.datetime.today().strftime("%Y")
    season = str(season)
    start_dt = season + '-03-01' #opening day is always late march or early april
    end_dt = season + '-11-01' #season is definitely over by November 
    return(pitching_stats_range(start_dt, end_dt))