'too many values to unpack', iterating over a dict. key=>string, value=>list

I am getting the too many values to unpack error. Any idea how I can fix this?

first_names = ['foo', 'bar']
last_names = ['gravy', 'snowman']

fields = {
    开发者_StackOverflow'first_names': first_names,
    'last_name': last_names,
}        

for field, possible_values in fields:  # error happens on this line

Python 3

Use items().

for field, possible_values in fields.items():
    print(field, possible_values)

Python 2

Use iteritems().

for field, possible_values in fields.iteritems():
    print field, possible_values

See this answer for more information on iterating through dictionaries, such as using items(), across Python versions.

For reference, iteritems() was removed in Python 3.

For Python 3.x iteritems has been removed. Use items instead.

for field, possible_values in fields.items():
    print(field, possible_values)

You want to use iteritems. This returns an iterator over the dictionary, which gives you a tuple(key, value)

>>> for field, values in fields.iteritems():
...     print field, values
... 
first_names ['foo', 'bar']
last_name ['gravy', 'snowman']

Your problem was that you were looping over fields, which returns the keys of the dictionary.

>>> for field in fields:
...     print field
... 
first_names
last_name

For lists, use enumerate

for field, possible_values in enumerate(fields):
    print(field, possible_values)

iteritems will not work for list objects

you are missing fields.iteritems() in your code.

You could also do it other way, where you get values using keys in the dictionary.

for key in fields:
    value = fields[key]

Can't be iterating directly in dictionary. So you can through converting into tuple.

first_names = ['foo', 'bar']
last_names = ['gravy', 'snowman']

fields = {
    'first_names': first_names,
    'last_name': last_names,
         } 
tup_field=tuple(fields.items())
for names in fields.items():
     field,possible_values = names
     tup_possible_values=tuple(possible_values)
     for pvalue in tup_possible_values:
           print (field + "is" + pvalue)

In Python3 iteritems() is no longer supported

Use .items

for field, possible_values in fields.items():
    print(field, possible_values)

Just thought I'd throw this in. I have the "too many values to unpack (expected 2)" crop up today. Infuriating but is was due to missing a comma in a choice list.

CapTextureChoices = [
("initial", ""),
("Shaggy", "Shaggy"),
("Wrinkled", "Wrinkled"),
("Striate," "Striate"),
("Downy", "Downy")
]

the missing comma between "Striate," "Striate" was the culprit