Formatting structured data in Python - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to convert the dictionary to a JSON string.

Python

import json

person = {"name": "Alice", "age": 30}
json_str = json.[1](person)
print(json_str)

Drag options to blanks, or click blank then click option'

Adumps

Bloads

Cload

Ddump

Attempts:

3 left

💡 Hint

Common Mistakes

Using json.load or json.loads instead of json.dumps

Confusing dump and dumps functions

The json.dumps() function converts a Python object into a JSON string.

2fill in blank

medium

Complete the code to pretty-print the JSON string with indentation.

Python

import json

data = {"city": "Paris", "population": 2148327}
pretty_json = json.dumps(data, [1]=4)
print(pretty_json)

Drag options to blanks, or click blank then click option'

Aensure_ascii

Bsort_keys

Cseparators

Dindent

Attempts:

3 left

💡 Hint

Common Mistakes

Using sort_keys instead of indent

Forgetting to set indent to a number

The indent parameter adds spaces to format the JSON string nicely.

3fill in blank

hard

Fix the error in the code to load JSON data from a string.

Python

import json

json_data = '{"fruit": "apple", "count": 10}'
data = json.[1](json_data)
print(data)

Drag options to blanks, or click blank then click option'

Aloads

Bdumps

Cload

Ddump

Attempts:

3 left

💡 Hint

Common Mistakes

Using json.load instead of json.loads

Using json.dumps or json.dump which write JSON

The json.loads() function reads a JSON string and converts it to a Python object.

4fill in blank

hard

Fill both blanks to create a dictionary comprehension that maps words to their lengths only if length is greater than 3.

Python

words = ["apple", "bat", "cat", "door"]
lengths = {word: [1] for word in words if [2] > 3}
print(lengths)

Drag options to blanks, or click blank then click option'

Alen(word)

Bword

Attempts:

3 left

💡 Hint

Common Mistakes

Using the word itself as the value instead of its length

Checking the word instead of its length in the condition

The first blank needs len(word) to get the length. The second blank also needs len(word) to check if length is greater than 3.

5fill in blank

hard

Fill all three blanks to create a dictionary comprehension that maps uppercase words to their counts only if count is positive.

Python

counts = {"apple": 2, "banana": 0, "cherry": 5}
result = { [1]: [2] for [3], count in counts.items() if count > 0 }
print(result)

Drag options to blanks, or click blank then click option'

Aword.upper()

Bcount

Cword

Dfruit

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong variable names in the loop

Not converting the word to uppercase for the key

The key is the uppercase word (word.upper()), the value is the count, and the loop variable is word.

Practice

1. What does the indent parameter do in json.dumps() when formatting structured data?

easy

A. Adds spaces and new lines to make the output easier to read

B. Converts data into a binary format

C. Removes all spaces and new lines for compact output

D. Encrypts the JSON data for security

Solution

1. Step 1: Understand the purpose of json.dumps()

   This function converts Python data into a JSON string.

2. Step 2: Role of indent parameter

   The indent parameter adds spaces and new lines to format the JSON string nicely for readability.

3. Final Answer:

   Adds spaces and new lines to make the output easier to read -> Option A

4. Quick Check:

   indent = readable JSON [OK]

Hint: Remember: indent means pretty print with spaces [OK]

Common Mistakes:

• Thinking indent compresses JSON
• Confusing indent with encryption
• Assuming indent changes data content

2. Which of the following is the correct syntax to format a Python dictionary data as a JSON string with indentation of 4 spaces?

easy

A. json.dumps(data, indent=4)

B. json.dumps(data, indent='4')

C. json.dumps(data, indent=True)

D. json.dumps(data, space=4)

Solution

1. Step 1: Check the correct parameter type for indent

   The indent parameter expects an integer number of spaces, not a string or boolean.

2. Step 2: Validate each option

   json.dumps(data, indent=4) uses indent=4 correctly. json.dumps(data, indent='4') uses a string '4' which is invalid. json.dumps(data, indent=True) uses boolean True which is invalid. json.dumps(data, space=4) uses a wrong parameter name space.

3. Final Answer:

   json.dumps(data, indent=4) -> Option A

4. Quick Check:

   Indent value must be integer [OK]

Hint: Use integer for indent, not string or boolean [OK]

Common Mistakes:

• Passing indent as a string instead of integer
• Using wrong parameter name like 'space'
• Passing boolean instead of number

3. What is the output of this code?

import json
data = {'name': 'Alice', 'age': 30}
print(json.dumps(data, indent=2))

medium

A. {"name": "Alice", "age": 30}

B. {
"name": "Alice",
"age": 30
}

C. {name: Alice, age: 30}

D. SyntaxError

Solution

1. Step 1: Understand json.dumps with indent=2

   The function converts the dictionary to a JSON string with 2 spaces indentation for each nested level.

2. Step 2: Check the output format

   The output will have new lines and spaces, keys and string values in double quotes, and numeric values as is.

3. Final Answer:

   { "name": "Alice", "age": 30 } -> Option B

4. Quick Check:

   Indent=2 adds spaces and new lines [OK]

Hint: Indent adds new lines and spaces for readability [OK]

Common Mistakes:

• Expecting compact JSON without spaces
• Using single quotes instead of double quotes
• Confusing Python dict print with JSON string

4. The following code throws an error. What is the mistake?

import json
data = {'x': 1, 'y': 2}
print(json.dumps(data, indent=2.0))

medium

A. json.dumps requires a second argument for separators

B. The data dictionary keys must be strings only

C. json.dumps cannot format dictionaries

D. The indent parameter should be an integer, not a float

Solution

1. Step 1: Identify the error cause

   The indent parameter is given as a float 2.0 instead of an integer 2.

2. Step 2: Understand parameter type requirements

   json.dumps expects indent to be an integer number of spaces for formatting, passing a float causes a TypeError.

3. Final Answer:

   The indent parameter should be an integer, not a float -> Option D

4. Quick Check:

   Indent must be int, not float [OK]

Hint: Check indent type: must be integer, not float [OK]

Common Mistakes:

• Passing indent as float instead of int
• Thinking keys must be strings for json.dumps
• Expecting separators argument is mandatory

5. You have a list of dictionaries representing users:

users = [{'name': 'Bob', 'age': 25}, {'name': 'Eve', 'age': 28}]

How do you create a JSON string with indentation of 2 spaces and keys sorted alphabetically?

hard

A. json.dumps(users, indent='2', sort_keys=True)

B. json.dumps(users, indent=2, sort=True)

C. json.dumps(users, indent=2, sort_keys=True)

D. json.dumps(users, pretty=2, sort_keys=True)

Solution

1. Step 1: Use json.dumps with indent and sort_keys

   The indent parameter formats the JSON with spaces and new lines. The sort_keys=True sorts dictionary keys alphabetically.

2. Step 2: Validate correct parameter names and types

   json.dumps(users, indent=2, sort_keys=True) uses correct parameters and types. json.dumps(users, indent=2, sort=True) uses invalid parameter sort. json.dumps(users, indent='2', sort_keys=True) passes indent as string which is invalid. json.dumps(users, pretty=2, sort_keys=True) uses invalid parameter pretty.

3. Final Answer:

   json.dumps(users, indent=2, sort_keys=True) -> Option C

4. Quick Check:

   Use indent=int and sort_keys=True [OK]

Hint: Use sort_keys=True and indent as integer [OK]

Common Mistakes:

• Using wrong parameter names like sort or pretty
• Passing indent as string
• Forgetting sort_keys to sort keys