JSON out

Write the codeEasy 2 stages

At the end of each day, the mission dashboard sends a summary to the archive, and the archive only takes JSON. The summary already exists as a Python dict. Printing it with print(summary) looks close, but single quotes, True and None aren't JSON, and the archive rejects it.

Produce real JSON text, laid out so a person can read it too.

Turn summary into JSON text indented by 2 spaces, store it in text, and print it:

{
  "mission": "Lumen-3",
  "agency": "JAXA",
  "ground_station": "Toru\u0144",
  "orbits": 12,
  "max_temp_c": 455.2,
  "alerts": [
    "Battery 3 temperature high",
    "Star tracker lost lock"
  ],
  "crewed": false,
  "next_pass": null
}

Use json.dumps(summary, indent=2). Look at what False, None and Toruń turned into.

Indented JSON

Real JSON in text

Finish stage 1 to unlock this stage.

Keep Toruń readable with ensure_ascii=False, and sort the keys with sort_keys=True, so that two days' files line up when compared:

{
  "agency": "JAXA",
  "alerts": [
    "Battery 3 temperature high",
    "Star tracker lost lock"
  ],
  "crewed": false,
  "ground_station": "Toruń",
  "max_temp_c": 455.2,
  "mission": "Lumen-3",
  "next_pass": null,
  "orbits": 12
}

Readable and sorted

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Hints

Import System Modules

import-system-modules.py

# A module is a toolbox someone else already built and tested for you

# Plain import brings in the whole module
import sys
import platform
import math

# from ... import brings in just one tool
from math import sqrt

# as gives a module a shorter nickname
import random as rng

# With a plain import: module name, a dot, then the tool
print("Python version:", platform.python_version())
print("Running on:", platform.system())
print("Python lives at:", sys.executable)

# math carries constants you would not want to type from memory
radius_km = 6371
print("Earth circumference:", round(2 * math.pi * radius_km), "km")

# sqrt arrived on its own, so it needs no dot in front
print("Square root of 9:", sqrt(9))

# rng is simply a nickname for random
print("Random sol of the Martian year:", rng.randint(1, 687))

Open the full example

script.py

PythonLn 1, Col 1Spaces: 4

Loading the Python environment…

Command-line arguments (sys.argv)

Separate arguments with commas. They're passed on every Run as sys.argv[1:].