如何拆分Pandas DataFrameGroupBy

def split_df_into_num_chunks(cls, df, chunks = 10): 
    list_of_df = list()
    initial_len = len(df.index)
    chunk_size = initial_len // chunks
    for i in range(chunks):
        list_of_df.append(df[i*chunk_size:(i+1)*chunk_size])
    if (i+1)*chunk_size < initial_len:
        list_of_df.append(df[(i+1)*chunk_size:initial_len])
    return list_of_df

然而,我无法计算出如何按eg拆分DataFrameGroupBy

    id        date                            qty
0  540689582 2017-09-22 00:00:00+00:00        41
1  540689582 2017-09-23 00:00:00+00:00        44
2  540689582 2017-09-24 00:00:00+00:00        52
3  540689583 2017-09-22 00:00:00+00:00        56
4  540689583 2017-09-23 00:00:00+00:00        31

我想把DataFrameGroupBy拆分成n个大小大致相等的子DataFrameGroupBy,我想保留id的组(即保持每个组不变,拆分时在组之间拆分)