avoiding duplication in yaml files. Heard about from @beerops https://twitter.com/beerops/status/647499854499987456 then googled and found https://gist.github.com/bowsersenior/979804

data.yml

default: &DEFAULT
  URL:          stooges.com
  throw_pies?:  true  
  stooges:  &stooge_list
    larry:  first_stooge
    moe:    second_stooge
    curly:  third_stooge
  
development:
  <<: *DEFAULT
  URL:      stooges.local
  stooges: 
    shemp: fourth_stooge
    
test:
  <<: *DEFAULT
  URL:    test.stooges.qa
  stooges: 
    <<: *stooge_list
    shemp: fourth_stooge

read.py

import os
import pprint
import yaml  # https://pypi.python.org/pypi/PyYAML


file_path = os.path.join(os.path.dirname(__file__), 'data.yml')

with open(file_path, 'r') as f:
    yaml_data = f.read()
    parsed_data = yaml.load(yaml_data)
    pprint.pprint(parsed_data)