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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 team_pitching(start_season, end_season=None, league='all', ind=1):
 """ Get season-level pitching data aggregated by team. ARGUMENTS: start_season : int : first season you want data for (or the only season if you do not specify an end_season) end_season : int : final season you want data for league : "all", "nl", or "al" ind : int : =1 if you want individual season level data, =0 if you want a team'ss aggreagate data over all seasons in the query """

    if start_season is None:
        raise ValueError("You need to provide at least one season to collect data for. Try team_pitching(season) or team_pitching(start_season, end_season).")
    if end_season is None:
        end_season = start_season
    soup = get_soup(start_season=start_season, end_season=end_season, league=league, ind=ind)
    table = get_table(soup, ind)
    table = postprocessing(table)
    return table