R 从一个列表的框架中移除列表包装器

df <- structure(list(DateOpened = list(DateOpened = list("2022-07-15T00:00:00"), 
    DateOpened = list("2022-10-03T08:53:38.147"), DateOpened = list(
        "2021-04-01T00:00:00"), DateOpened = list("2022-09-12T00:00:00"), 
    DateOpened = list("2023-01-01T00:00:00"), DateOpened = list(
        "2023-04-11T18:56:08.467"), DateOpened = list("2023-05-09T09:20:51.903"), 
    DateOpened = list("2022-10-03T00:00:00"), DateOpened = list(
        "2022-09-12T00:00:00"), DateOpened = list("2021-04-01T00:00:00"), 
    DateOpened = list("2024-02-26T15:53:12.327"), DateOpened = list(
        "2024-02-26T16:10:02.563")), DateClosed = list(DateClosed = structure(list(), nil = "true"), 
    DateClosed = list("2023-06-01T00:00:00"), DateClosed = structure(list(), nil = "true"), 
    DateClosed = structure(list(), nil = "true"), DateClosed = structure(list(), nil = "true"), 
    DateClosed = structure(list(), nil = "true"), DateClosed = list(
        "2023-10-31T00:00:00"), DateClosed = list("2023-06-22T00:00:00"), 
    DateClosed = structure(list(), nil = "true"), DateClosed = list(
        "2024-01-22T00:00:00"), DateClosed = structure(list(), nil = "true"), 
    DateClosed = structure(list(), nil = "true"))), row.names = c(NA, 
-12L), class = "data.frame")

我想让它成为一个只包含值的数据帧，而不是它们周围的列表.

我试了as.data.frame(lapply, '[[', 1)个 ([[]和[[])没有效果和list_flatten，它产生了一个列表，而不是一个列表.