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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 get_protein_id_list(df, level=0):
 """ Return a complete list of shortform IDs from a DataFrame Extract all protein IDs from a dataframe from multiple rows containing protein IDs in MaxQuant output format: e.g. P07830;P63267;Q54A44;P63268 Long names (containing species information) are eliminated (split on ' ') and isoforms are removed (split on '_'). :param df: DataFrame :type df: pandas.DataFrame :param level: Level of DataFrame index to extract IDs from :type level: int or str :return: list of string ids """

    protein_list = []
    for s in df.index.get_level_values(level):
        protein_list.extend( get_protein_ids(s) )

    return list(set(protein_list))