Accessing elements of Python dictionary by index

Question

Consider a dict like

mydict = {
  \'Apple\': {\'American\':\'16\', \'Mexican\':10, \'Chinese\':5},
  \'Grapes\':{\'Arabian\':\'25\',\'Indian\':\'20\'} }
         


        

Answer 1

With the following small function, digging into a tree-shaped dictionary becomes quite easy:

def dig(tree, path):
    for key in path.split("."):
        if isinstance(tree, dict) and tree.get(key):
            tree = tree[key]
        else:
            return None
    return tree

Now, dig(mydict, "Apple.Mexican") returns 10, while dig(mydict, "Grape") yields the subtree {'Arabian':'25','Indian':'20'}. If a key is not contained in the dictionary, dig returns None.

Note that you can easily change (or even parameterize) the separator char from '.' to '/', '|' etc.