Python中的多层列表迭代

Question

I am trying to iterate through multi-layered lists in Python and am encountering an error.

example = [
    [ ("Set 1"),
      [ ('a', 'b', 'c'),
        ('d', 'e', 'f')
      ]
    ],
    [ ("Set 2"),
      [ ('1', '2', '3'),
        ('4', '5', '6')
      ]
    ]
]

for section in example:
    print("Section: ", section)
    for section_name, section_vals in section:
        print("Name: ", section_name)
        print("Values: ", section_vals)

The error I am getting is: ValueError: too many values to unpack (expected 2)

The output I am expecting to see is:

Section: ['Set 1', [('a', 'b', 'c'), ('d', 'e', 'f')]]
Name: 'Set 1'
Values: ('a', 'b', 'c'), ('d', 'e', 'f')
Section: ['Set 1', [('1', '2', '3'), ('4', '5', '6')]]
Name: 'Set 2'
Values: ('1', '2', '3'), ('4', '5', '6')

Maybe it's just been a long day for me but I can't seem to figure out my error.

Answer 1

You don't need the inner for loop. Thus, the code should look like:

for section in example:
    print("Section: ", section)
    section_name, section_vals=section
    print("Name: ", section_name)
    print("Values: ", section_vals)

And then the output is:

Section:  ['Set 1', [('a', 'b', 'c'), ('d', 'e', 'f')]]
Name:  Set 1
Values:  [('a', 'b', 'c'), ('d', 'e', 'f')]
Section:  ['Set 2', [('1', '2', '3'), ('4', '5', '6')]]
Name:  Set 2
Values:  [('1', '2', '3'), ('4', '5', '6')]

Answer 2

The other answers are correct. Just to add that you can directly unpack the list:

for section_name, section_vals in example:
    print("Name: ", section_name)
    print("Values: ", section_vals)