How to Find All Occurrences of a Key in Nested Dictionaries and Lists?

Find All Occurrences of a Key in Nested Dictionaries and Lists

This problem presents a dictionary with arbitrary depth of nesting, containing lists and dictionaries. The goal is to extract the values of every key "id" within the structure.

Solution:

The following functions offer various approaches to traverse the nested data structure and retrieve the "id" values:

1. gen_dict_extract(k,o): This function utilizes a recursive generator to navigate the dictionary and lists. It checks for the "iteritems" function to handle both Python 2 and 3 versions.
2. find_all_items(k,o): Similar to the first approach, this function uses recursion and iteration to extract the "id" values.
3. findkeys(k,o): This function leverages the "isinstance" method to identify lists and dictionaries within the structure. It uses nested "for" loops to iterate through the data and locate "id" keys.
4. get_recursively(k,o): This function combines the principles of recursion and comprehensions to traverse the nesting and search for the target key.
5. find(k,o): Utilizing a simplified recursive approach, this function traverses the dictionary and lists to extract "id" values.
6. dict_extract(k,o): Similar to the find function, this function uses a slightly simpler recursive approach to locate "id" values within the structure.

Performance Comparison:

After testing the functions against a complex dictionary object, the gen_dict_extract function emerged as the fastest, while the find_all_items function underperformed significantly. The other functions exhibited similar performance, with find and keyHole being limited to string search operations.

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