dict( [1,2] ) # TypeError: cannot convert dictionary update sequence element #0 to a sequence #

dict(
    [1,2]
)
# TypeError: cannot convert dictionary update sequence element #0 to a sequence
# list tuple set 都可以, 并且
list(
    list(
        [1,2]
    )
) == [1,2]  # 仍然是[1,2]

list(
    {"key": "value"}
)  # 只保留键名