Python make dict from list | Example code

Using dictionary comprehension, dict fromkeys(), or the zip() methods can make a dict form list in Python. Thees All methods create a new dictionary and not modify the existing list.

Python makes dictionary from list example

Simple example code.

Dictionary Comprehension

fruit_list = ["Apple", "Pear", "Peach", "Banana"]

fruit_dict = {fruit: "In stock" for fruit in fruit_list}

print(fruit_dict)

Output:

Python make dict from list

Using dict.fromkeys()

This method accepts a list of keys that turn into a dictionary. Optionally, can specify a value to assign to every key.

Without value

fruits = ["Apple", "Pear", "Peach", "Banana"]

fruit_dict = dict.fromkeys(fruits)

print(fruit_dict)

Output: {‘Apple’: None, ‘Pear’: None, ‘Peach’: None, ‘Banana’: None}

With values

Assign ‘Yes’ to every element value.

fruits = ["Apple", "Pear", "Peach", "Banana"]

fruit_dict = dict.fromkeys(fruits, "Yes")

print(fruit_dict)

Output: {‘Apple’: ‘Yes’, ‘Pear’: ‘Yes’, ‘Peach’: ‘Yes’, ‘Banana’: ‘Yes’}

Using zip() method

The zip() method is useful if you want to merge two lists into a dictionary. It’s actually making a dictionary from two lists.

fruits = ["Apple", "Pear", "Peach", "Banana"]
prices = [80, 50, 60, 30]

fruit_dict = dict(zip(fruits, prices))

print(fruit_dict)

Output: {‘Apple’: 80, ‘Pear’: 50, ‘Peach’: 60, ‘Banana’: 30}

How to make a dictionary from a list in python example

Answer: As Upper examples, you can use any one of the methods to make a dictionary from a list in python. But if you want to create a dictionary with key-value from only a single list then check the below examples.

dict comprehension

def create(lst):
    res = {lst[i]: lst[i + 1] for i in range(0, len(lst), 2)}
    return res


# Driver code
lst = ['a', 1, 'b', 2, 'c', 3]
print(create(lst))

Using zip() method

def create(a):
    it = iter(a)
    res = dict(zip(it, it))
    return res


# Driver code
lst = ['a', 1, 'b', 2, 'c', 3]
print(create(lst))

Output: {‘a’: 1, ‘b’: 2, ‘c’: 3}

Do comment if you have any doubts and suggestions on this Python dict list tutorial.

Note: IDE: PyCharm 2021.1.3 (Community Edition)

Windows 10

Python 3.7

All Python Examples are in Python 3, so Maybe its different from python 2 or upgraded versions.


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