Default Dict

---

examples/dictionary/counter.py

counter = {}

word = 'eggplant'

counter[word] += 1
# counter[word] = counter[word] + 1

Traceback (most recent call last):
  File "counter.py", line 5, in <module>
    counter[word] += 1
KeyError: 'eggplant'

examples/dictionary/counter_condition.py

counter = {}

word = 'eggplant'

if word not in counter:
    counter[word] = 0
counter[word] += 1

print(counter)

{'eggplant': 1}

examples/dictionary/default_dict.py

from collections import defaultdict

counter = defaultdict(int)

word = 'eggplant'

counter[word] += 1

print(counter)

defaultdict(<class 'int'>, {'eggplant': 1})