For dict in Python

In Python, a dictionary is a key-value mapping. Every value is mapped to one key. A dictionary can have zero or more elements.

The dictionary below has 3 pairs, each pair has one value. 'a' is mapped to 1, 'b' is mapped to 2, 'c' is mapped to 3.

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

You can loop over a dictionary using a for loop.

This works differently in Python 3 and Python 2. If you are still using Python 2, I recommend switching over to Python 3.

For Python 3.x:

    for key, value in d.items():

For Python 2.x:

    for key, value in d.iteritems():

For dict example

This Python 3 example loops over the dictionary d and outputs the key value pairs from beginning to last. Keep in mind that a dictionary is not required to keep its order.

d = {'a': 1, 'b': 2, 'c': 3}
for key, value in d.items():
    print(key)
    print(value)

If you only want the keys, you can use this code:

for key in d:
    print(key)

To use the value without the key, just ignore the key value in:

d = {'a': 1, 'b': 2, 'c': 3}
for key, value in d.items():

Related links:

• Dictionary in Python docs
• Learn Python

Comments

[Floris Lambrechts]

You can use values() instead of items() if you don't need the keys.