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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 bwar_pitch(return_all=False):
 """ Get data from war_daily_pitch table. Returns WAR, its components, and a few other useful stats. To get all fields from this table, supply argument return_all=True. """

    url = "http://www.baseball-reference.com/data/war_daily_pitch.txt"
    s = requests.get(url).content
    c=pd.read_csv(io.StringIO(s.decode('utf-8')))
    if return_all:
        return c
    else:
        cols_to_keep = ['name_common', 'mlb_ID', 'player_ID', 'year_ID', 'team_ID', 'stint_ID', 'lg_ID',
                        'G', 'GS', 'RA','xRA', 'BIP', 'BIP_perc','salary', 'ERA_plus', 'WAR_rep', 'WAA',
                        'WAA_adj','WAR']
        return c[cols_to_keep]