How to extract dictionary single key-value pair in variables
Add another level, with a tuple (just the comma):
(k, v), = d.items()
or with a list:
[(k, v)] = d.items()
or pick out the first element:
k, v = d.items()[0]
The first two have the added advantage that they throw an exception if your dictionary has more than one key, and both work on Python 3 while the latter would have to be spelled as k, v = next(iter(d.items()))
to work.
Demo:
>>> d = {'foo': 'bar'}
>>> (k, v), = d.items()
>>> k, v
('foo', 'bar')
>>> [(k, v)] = d.items()
>>> k, v
('foo', 'bar')
>>> k, v = d.items()[0]
>>> k, v
('foo', 'bar')
>>> k, v = next(iter(d.items())) # Python 2 & 3 compatible
>>> k, v
('foo', 'bar')
items()
returns a list of tuples so:
(k,v) = d.items()[0]
>>> d = {"a":1}
>>> [(k, v)] = d.items()
>>> k
'a'
>>> v
1
Or using next
, iter
:
>>> k, v = next(iter(d.items()))
>>> k
'a'
>>> v
1
>>>
d = {"a": 1}
you can do
k, v = d.keys()[0], d.values()[0]
d.keys()
will actually return list of all keys and d.values()
return list of all values, since you have a single key:value pair in d
you will be accessing the first element in list of keys and values
This is best if you have many items in the dictionary, since it doesn't actually create a list but yields just one key-value pair.
k, v = next(d.iteritems())
Of course, if you have more than one item in the dictionary, there's no way to know which one you'll get out.