Creating a Dictionary from a List of 2-Tuples
I have a list of 2-tuples like this:
l = [('a', 1), ('b', 2)]
and I want to be able to map this onto a dictionary object, so that I can do something like
l.a #=> 1
So I tried this, but why does it fail?
d = reduce(lambda y,x : y.update({x开发者_如何学Go[0]:x[1]}),l,{})
This gives the error:
AttributeError: 'NoneType' object has no attribute 'update'
What am I doing wrong?
>>> l = [('a', 1), ('b', 2)]
>>> d = dict(l)
>>> d['a']
1
Why not just do this:
d = dict(l)
Also, to answer your question, your solution is failing because y
(which is a 2-tuple) has no method update, since it's not a dict. Thankfully, what you're doing is built right in.
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