Hey Coder,

"When you can't get the right output...
... at least try to get some pretty output.
-- Nobody

Well, obviously, nobody said this.

But that doesn't prevent me from showing you how to "pretty print" Python objects.

Pretty-printing simply means to format program output in an aesthetically pleasing manner.

Python's built in print function does a decent job at printing objects.

However, it does get a bit messy sometimes.

For instance, if you load a JSON file into a dictionary, and to print it, you get something like this:

{'_id': '6683cde2a45341ca5c7a4c24', 'index': 5, 'isActive': False, 'balance': '$2,664.96', 'picture': 'http://example.com/', 'age': 40, 'eyeColor': 'brown', 'name': 'Butter Toast', 'company': 'MINITOX', 'email': 'buttertoast@domain.com', 'address': '374 Lorimer Street, Nadine, Minnesota, 8236', 'about': 'Laborum aliquip qui enim eiusmod dolore ea qui Lorem mollit culpa. Non consectetur duis fugiat irure tempor et culpa ullamco est nostrud commodo nostrud nulla. Occaecat eiusmod qui elit fugiat ullamco cillum ipsum dolor ullamco. Commodo elit reprehenderit eu consectetur incididunt adipisicing enim. Sunt dolor Lorem consectetur sunt ipsum anim amet id amet aliquip pariatur laborum cupidatat exercitation. Proident enim nulla elit sunt esse. Esse mollit non anim ipsum deserunt ad ad ullamco cupidatat Lorem tempor officia.\r\n', 'registered': '2019-02-21T09:14:47 -06:-30', 'latitude': 22.579932, 'longitude': 141.315732, 'tags': ['consectetur', 'dolor', 'fugiat', 'ullamco', 'quis', 'quis', 'cupidatat'], 'friends': [{'id': 0, 'name': 'Sherman Summers'}, {'id': 1, 'name': 'Finch Carney'}, {'id': 2, 'name': 'Velasquez Maddox'}], 'greeting': 'Hello, Butter Toast! You have 8 unread messages.', 'favoriteFruit': 'strawberry'}

This is an unreadable mess.

Sure, I could iterate manually thorough the dict, and make sure the rendering is neat.

But why do the work when the Python already has it covered?

Instead, we can simply import pprint from the standard library, like so:

from pprint import pprint

Then we simply pass it the dictionary to be printed:

pprint(json_dict)  # Assuming the data is present in json_dict

This gives the much better formatted output:

{'_id': '6683cde2a45341ca5c7a4c24',
 'about': 'Laborum aliquip qui enim eiusmod dolore ea qui Lorem mollit culpa. '
          'Non consectetur duis fugiat irure tempor et culpa ullamco est '
          'nostrud commodo nostrud nulla. Occaecat eiusmod qui elit fugiat '
          'ullamco cillum ipsum dolor ullamco. Commodo elit reprehenderit eu '
          'consectetur incididunt adipisicing enim. Sunt dolor Lorem '
          'consectetur sunt ipsum anim amet id amet aliquip pariatur laborum '
          'cupidatat exercitation. Proident enim nulla elit sunt esse. Esse '
          'mollit non anim ipsum deserunt ad ad ullamco cupidatat Lorem tempor '
          'officia.\r\n',
 'address': '374 Lorimer Street, Nadine, Minnesota, 8236',
 'age': 40,
 'balance': '$2,664.96',
 'company': 'MINITOX',
 'email': 'buttertoast@domain.com',
 'eyeColor': 'brown',
 'favoriteFruit': 'strawberry',
 'friends': [{'id': 0, 'name': 'Sherman Summers'},
             {'id': 1, 'name': 'Finch Carney'},
             {'id': 2, 'name': 'Velasquez Maddox'}],
 'greeting': 'Hello, Butter Toast! You have 8 unread messages.',
 'index': 5,
 'isActive': False,
 'latitude': 22.579932,
 'longitude': 141.315732,
 'name': 'Butter Toast',
 'picture': 'http://example.com/',
 'registered': '2019-02-21T09:14:47 -06:-30',
 'tags': ['consectetur',
          'dolor',
          'fugiat',
          'ullamco',
          'quis',
          'quis',
          'cupidatat']}

Notice a few changes:

- Keys go to new lines

- Dict keys are sorted by alphebetical order

- Long strings are broken into smaller chunks

This makes the output much more readable.

Of course, I used a JSON file for the demo, but pretty printing can be applied to anywhere use print.

So, next time print gives you messy output, give pprint a shot.

What about pretty printing CSV files or other tabular data?

For that we have options such as Rich, tabulate, and PrettyTable.

However, they're not part of the standard library.

Maybe we'll do articles on one of those too, but that would have to be some other time.

Co3

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