Write a function cat_some(d, ks) that receives a dictionary d and a list of possible keys ks. The keys of d are integers. The values are lists of integers. The returned result must be the concatenation of the lists corresponding in d to the keys in ks, in the same order the corresponding keys appear in ks. Integers in ks that do not appear in d contribute an empty list to the result.
Observation
Please make sure to remove or comment out from the Jutge submission any doctesting code you might have in your source code.
>>> cat_some({ 55: [0, 1, 4], 30: [-7, 7], 0: [0] }, [30, 55]) [-7, 7, 0, 1, 4] >>> cat_some({ 55: [0, 1, 4], 30: [-7, 7], 0: [0], 2345: [ 23, 4, 56 ] }, [ 0, 1, 2, 55, 0 ]) [0, 0, 1, 4, 0] >>> cat_some({ 55: [0, 1, 4], 30: [0] }, [ 66, 55 ]) + cat_some({ 55: [0, 1, 4], 30: [0] }, [ 66, 55 ]) [0, 1, 4, 0, 1, 4] >>> cat_some({ }, [ ]) []