如何将分隔文件中的某些列作为行取消透视？

def unpivot(file_path, delimiter, pivot_columns):
    data = {}
    with open(file_path, 'r') as file:
        for line in file:
            columns = line.strip().split(delimiter)
            identifier = tuple(columns[i] for i in pivot_columns)
            if identifier not in data:
                data[identifier] = []
            data[identifier].extend(columns[:pivot_columns[0]] + columns[pivot_columns[-1]+1:])
    
    # 输出取消透视后的数据
    for identifier, values in data.items():
        print(f'Identifier: {identifier}')
        print(f'Values: {values}')
        print('---')

# 示例调用
file_path = 'data.csv'
delimiter = ','
pivot_columns = [0, 1]  # 假设第0列和第1列为需要取消透视的列
unpivot(file_path, delimiter, pivot_columns)