Config File Formats: Practice Questions

For each snippet, write the output, the exception type, or “Runs Forever.” If it prints nothing, write “No Output”.

Question 1

import yaml

settings = yaml.safe_load("""
users:
  - name: Ada
    tags: [python, web]
  - name: Grace
    tags: [compilers]
""")
print(settings['users'][1]['name'])
print(settings['users'][0]['tags'][1])

Answer

Grace
web

Question 2

import yaml

settings = yaml.safe_load("""
welcome: |
  Hello!
  Welcome back.
summary: >
  Two posts
  this week.
""")
print(repr(settings['welcome']))
print(repr(settings['summary']))

Answer

'Hello!\nWelcome back.\n'
'Two posts this week.\n'

Question 3

import yaml

unquoted = yaml.safe_load('on: push')
quoted = yaml.safe_load('"on": push')
print(unquoted[True])
print('on' in unquoted)
print('on' in quoted)

Answer

push
False
True

Question 4

import yaml

settings = yaml.safe_load("""
version: 3.10
release: "3.10"
enabled: no
country: "no"
""")
print(settings['version'])
print(settings['release'])
print(settings['enabled'])
print(settings['country'])

Answer

3.1
3.10
False
no

Question 5

import tomllib

settings = tomllib.loads("""
title = "My Blog"

[owner]
name = "Ada"

[export.csv]
columns = ["username", "text"]
header = true
""")
print(settings['title'])
print(settings['owner']['name'])
print(settings['export']['csv']['columns'][-1])

Answer

My Blog
Ada
text

Question 6

import tomllib

settings = tomllib.loads("""
[export]
formats = ["json", "csv"]
options = {header = true, delimiter = ","}

[owner]
name = "Grace"
active = false
""")
print(settings['export']['options']['delimiter'])
print(settings['export']['options']['header'])
print('active' in settings['export'])
print(settings['owner']['active'])

Answer

,
True
False
False