find.py

import re
import yaml

def find(element, dictionary):
  """
  Find a value given a path like a.b.c
  """
    keys = element.split('.')
    rv = dictionary
    for key in keys:
        if re.search('\\[\\d+\\]', key):
            key = int(re.search('\\d+', key).group())
        rv = rv[key]
    return rv
  
if __name__ == '__main__':

    # Example from here: https://www.cloudbees.com/blog/yaml-tutorial-everything-you-need-get-started
    example_yaml = """
         doe: "a deer, a female deer"
         ray: "a drop of golden sun"
         pi: 3.14159
         xmas: true
         french-hens: 3
         calling-birds:
           - huey
           - dewey
           - louie
           - fred
         xmas-fifth-day:
           calling-birds: four
           french-hens: 3
           golden-rings: 5
           partridges:
             count: 1
             location: "a pear tree"
           turtle-doves: two
    """

    example = yaml.load(example_yaml, Loader=yaml.FullLoader)

    assert find("xmas-fifth-day.partridges.count", example) == 1
    assert find("calling-birds.[0]", example) == "huey"

The method find lets you access values in a dict using a path notation. Note that there are a few cases where this might fail. For example when using [ in keys.