Dictionary Methods

keys(), values(), items(), get(), update() — the essential toolkit for working with dictionaries.

"keys(), values(), items() — three methods that unlock everything inside a dictionary. Learn these and you can work with any dict."

— ShurAI

The Big Four Methods

.keys()

Returns all keys in the dictionary

.values()

Returns all values in the dictionary

.items()

Returns all (key, value) pairs — use with loops

.get(key)

Safe lookup — returns None if key missing (no crash)

python — keys, values, items

student = {"name": "Kavya", "score": 91, "city": "Pune"}

print(student.keys())    # dict_keys(['name', 'score', 'city'])
print(student.values())  # dict_values(['Kavya', 91, 'Pune'])
print(student.items())   # dict_items([('name','Kavya'),('score',91),...])

# Most common use — loop with items()
for key, val in student.items():
    print(f"  {key}: {val}")

get() — Safe Lookup, No Crash

Using dict["key"] raises a KeyError if the key doesn't exist. get() returns None instead — much safer:

python

scores = {"Riya": 88, "Arjun": 75}

# Dangerous — crashes if key missing
# print(scores["Sneha"])   # KeyError!

# Safe — returns None if missing
print(scores.get("Riya"))     # 88
print(scores.get("Sneha"))    # None

# Provide a default value if key missing
print(scores.get("Sneha", 0))  # 0  (default)

# Practical pattern
name = input("Student name: ")
result = scores.get(name, "not found")
print(f"{name}: {result}")

update() — Merge Another Dict

python

profile = {"name": "Riya", "age": 22}
extra   = {"city": "Mumbai", "age": 23}  # age will be updated

profile.update(extra)
print(profile)
# {'name': 'Riya', 'age': 23, 'city': 'Mumbai'}

pop() and clear()

python

d = {"a": 1, "b": 2, "c": 3}

# pop() — remove key and return its value
val = d.pop("b")
print(val)   # 2
print(d)     # {'a': 1, 'c': 3}

# clear() — remove all entries
d.clear()
print(d)     # {}

Real Example — Word Frequency Counter

python

sentence = "the cat sat on the mat the cat is fat"
words    = sentence.split()
freq     = {}

for word in words:
    freq[word] = freq.get(word, 0) + 1

for word, count in sorted(freq.items(), key=lambda x: -x[1]):
    print(f"  {word:6} x{count}")

output

  the    x3
  cat    x2
  sat    x1
  on     x1
  mat    x1
  is     x1
  fat    x1

"get() with a default is one of Python's most practical patterns. Use it whenever a key might or might not be there."

— ShurAI

🧠 Quiz — Q1

What does dict.get("key", 0) return if "key" does not exist?

🧠 Quiz — Q2

Which method returns (key, value) pairs for looping?

🧠 Quiz — Q3

What does d.pop("name") do?

🧠 Quiz — Q4

In the word-frequency pattern freq.get(word, 0) + 1, what does the 0 do?