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This tutorial will show you how to pretty print dictionaries in Python. Pretty printing means presenting some printed content in a more readable format or style.

pprint()Pretty printing dictionaries in Python

pprintis a Python module that provides the ability to pretty print Python data types to make them more readable. This module also supports pretty printing dictionaries.

In pprintthe module, there is a function with the same name pprint(), which is used to pretty-print a given string or object.

First, we declare an array of dictionaries. After that, pprint.pprint()we pretty-print them using the function.

import pprint

dct_arr = [
    {"Name": "John", "Age": "23", "Country": "USA"},
    {"Name": "Jose", "Age": "44", "Country": "Spain"},
    {"Name": "Anne", "Age": "29", "Country": "UK"},
    {"Name": "Lee", "Age": "35", "Country": "Japan"},
]

pprint.pprint(dct_arr)

Output:

[{'Age': '23', 'Country': 'USA', 'Name': 'John'},
 {'Age': '44', 'Country': 'Spain', 'Name': 'Jose'},
 {'Age': '29', 'Country': 'UK', 'Name': 'Anne'},
 {'Age': '35', 'Country': 'Japan', 'Name': 'Lee'}]

By comparison, here is the output of a normal print()statement.

[
    {"Name": "John", "Age": "23", "Country": "USA"},
    {"Name": "Jose", "Age": "44", "Country": "Spain"},
    {"Name": "Anne", "Age": "29", "Country": "UK"},
    {"Name": "Lee", "Age": "35", "Country": "Japan"},
]

pprint()The output is definitely easier to read. What it does is break up each dictionary element in the array after the comma, while also sorting the dictionary values ​​by key.

If you don't want your key-value pairs to be sorted by the key, then pprint()is not suitable to use because its sorting mechanism is built into the function.

Also note that pprint()pretty printing of nested objects, including nested dictionaries, will not work. So if you want your values ​​to be nested, this is not the solution for this problem either.

json.dumps()Pretty printing a dictionary in Python using

In the Python jsonmodule, there is a dumps()function called which can convert a Python object into a JSON string. In addition to the conversion, it also formats the dictionary into a pretty JSON format, so this is a viable way to pretty-print the dictionary by converting it to JSON first.

dumps()The function accepts three arguments for pretty printing: the object to be converted, a boolean value sort_keysthat determines whether the elements should be sorted by key, and indent, which specifies the number of spaces to indent.

For this solution, we will use the same example dictionary as above. sort_keysSet to Falseto disable sorting and indentto 4a space.

import json

dct_arr = [
    {"Name": "John", "Age": "23", "Country": "USA"},
    {"Name": "Jose", "Age": "44", "Country": "Spain"},
    {"Name": "Anne", "Age": "29", "Country": "UK"},
    {"Name": "Lee", "Age": "35", "Country": "Japan"},
]

print(json.dumps(dct_arr, sort_keys=False, indent=4))

Output:

[
    {
        "Age": "23",
        "Country": "USA",
        "Name": "John"
    },
    {
        "Age": "44",
        "Country": "Spain",
        "Name": "Jose"
    },
    {
        "Age": "29",
        "Country": "UK",
        "Name": "Anne"
    },
    {
        "Age": "35",
        "Country": "Japan",
        "Name": "Lee"
    }
]

It is much more readable than pprint()the output of the function, although it takes up a few more lines, since it is in JSON format.

What if the given value has a nested dictionary inside it? Let's edit this example and see the output.

import json

dct_arr = [
    {"Name": "John", "Age": "23", "Residence": {"Country": "USA", "City": "New York"}},
    {"Name": "Jose", "Age": "44", "Residence": {"Country": "Spain", "City": "Madrid"}},
    {"Name": "Anne", "Age": "29", "Residence": {"Country": "UK", "City": "England"}},
    {"Name": "Lee", "Age": "35", "Residence": {"Country": "Japan", "City": "Osaka"}},
]

print(json.dumps(dct_arr, sort_keys=False, indent=4))

Output:

[
    {
        "Name": "John",
        "Age": "23",
        "Residence": {
            "Country": "USA",
            "City": "New York"
        }
    },
    {
        "Name": "Jose",
        "Age": "44",
        "Residence": {
            "Country": "Spain",
            "City": "Madrid"
        }
    },
    {
        "Name": "Anne",
        "Age": "29",
        "Residence": {
            "Country": "UK",
            "City": "England"
        }
    },
    {
        "Name": "Lee",
        "Age": "35",
        "Residence": {
            "Country": "Japan",
            "City": "Osaka"
        }
    }
]

It's clear that using json.dump()supports beautiful JSON nested dictionaries, which look visually clean and very readable even when nested.

yaml.dump()Pretty printing dictionaries in Python

Another way to print a dictionary is to use the yamlmodule's dump()print function. It works json.dumps()the same as the print function, but uses the YAML format instead of JSON.

First, pipinstall the YAML module using .

pip install pyyaml

Or if using Python 3 and pip3installing the YAML module.

pip3 install pyyaml

Let's try this with the same nesting example we used in the JSON example.

Note the new parameter default_flow_style, which determines whether the output style of dump should be inlineor block. In this case, the output should be in blocks, and since we want it to be readable, we set this parameter to False.

import yaml

dct_arr = [
    {"Name": "John", "Age": "23", "Residence": {"Country": "USA", "City": "New York"}},
    {"Name": "Jose", "Age": "44", "Residence": {"Country": "Spain", "City": "Madrid"}},
    {"Name": "Anne", "Age": "29", "Residence": {"Country": "UK", "City": "England"}},
    {"Name": "Lee", "Age": "35", "Residence": {"Country": "Japan", "City": "Osaka"}},
]

print(yaml.dump(dct_arr, sort_keys=False, default_flow_style=False))

Output:

- Name: John
  Age: '23'
  Residence:
    Country: USA
    City: New York
- Name: Jose
  Age: '44'
  Residence:
    Country: Spain
    City: Madrid
- Name: Anne
  Age: '29'
  Residence:
    Country: UK
    City: England
- Name: Lee
  Age: '35'
  Residence:
    Country: Japan
    City: Osaka

In conclusion, whether the YAML dump()function is more readable than JSON dumps()is a matter of personal opinion. It depends on personal preference or what type of output is needed. When it comes to more complex data structures or nested objects, both functions pprintare better than the output of .