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What is the cleanest way to update the values of multiple keys in a dictionary to the values stored in a tuple?
Example:
I want to go from
>>>mydict = {'a':None, 'b':None, 'c':None, 'd':None}
>>>mytuple = ('alpha', 'beta', 'delta')
to
>>>print mydict
{'a':'alpha', 'b':'beta', 'c':None, 'd':'delta'}
Is there an easy one-liner for this? Something like this seems to be getting close to what I want.
EDIT: I don't wish to assign values to keys based on their first letter. I'm just hoping for something like
mydict('a','b','d') = mytuple
Obviously that doesn't work, but I'm hoping for something similar to that.
277
If we want to update the values of multiple keys in the dictionary, then we can pass them as key-value pairs in the update() function. To bind keep multiple key-value pairs together, either we can use a list of tuples or we can create a temporary dictionary.
General Idea: In Python, if we want a dictionary to have multiple values for a single key, we need to store these values in their own container within the dictionary. To do so, we need to use a container as a value and add our multiple values to that container. Common containers are lists, tuples, and sets.
In order to update the value of an associated key, Python Dict has in-built method — dict. update() method to update a Python Dictionary. The dict. update() method is used to update a value associated with a key in the input dictionary.
If you're trying to create a new dictionary:
d = dict(zip(keys, valuetuple))
If you're trying to add to an existing one, just change the = to .update(…).
So, your example can be written as:
mydict.update(dict(zip('abd', mytuple))))
If you're doing this more than once, I'd wrap it up in a function, so you can write:
setitems(d, ('a', 'b', 'd'), mytuple)
Or maybe a "curried" function that parallels operator.itemgetter?
141
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