Dictionary Methods0%

Dictionary Methods

Beginner9 min readUpdated: 2026-09-03
Study Materials

Dictionary Methods

Dictionary view methods provide dynamic windows into keys, values, and pair tuples.


Key Concepts & Detailed Explanation

View methods:

  • .keys(): Dynamic view of all keys.
  • .values(): Dynamic view of all values.
  • .items(): Dynamic view of all (key, value) pairs.
  • .update(other_dict): Merges pairs from other_dict into this dict.
  • .setdefault(key, default): Returns key value; if key missing, inserts key with default.

Code Examples & Output

Python
course_info = {
"name": "Python for Beginners",
"duration": "1 Month",
"mode": "Both"
}
 
print("Keys:", list(course_info.keys()))
print("Values:", list(course_info.values()))
 
# Iterating over items
for key, value in course_info.items():
print(f" {key} -> {value}")
 
# setdefault
instructor = course_info.setdefault("instructor", "Er. Sumit Kumar")
print("Instructor:", instructor)

Expected Output:

Output
Keys: ['name', 'duration', 'mode']
Values: ['Python for Beginners', '1 Month', 'Both']
name -> Python for Beginners
duration -> 1 Month
mode -> Both
Instructor: Er. Sumit Kumar

Best Practices & Common Pitfalls

Iterating with 'for k, v in d.items():' is the most idiomatic way to loop through dictionaries in Python.


Practice Quiz

1. Which method yields an iterable of (key, value) tuples?

  • A) dict.pairs()
  • B) dict.items()
  • C) dict.entries()
  • D) dict.values()
Answer: B Explanation: dict.items() returns (key, value) tuples.

2. What does dict.setdefault('key', 'default') do if 'key' already exists?

  • A) Overwrites with default
  • B) Returns current value and does not overwrite
  • C) Raises KeyError
  • D) Deletes key
Answer: B Explanation: setdefault returns existing value without modifying if the key exists.

Practice Challenge

Merge two dictionaries of student contact details using the .update() method.

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Nested Dictionaries

Continue learning with hands-on practice, examples, and exercises in the upcoming topic.

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Copying DictionariesNested Dictionaries

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