How to merge Dictionaries with Python

There are lots of different ways to merge dictionaries in the Python.

Here are the methods you will learn about:

dict.update()
**
the | Union Operator

Let’s start with the update() method!

Using dict.update()

>>> first_dictionary = {"name": "Mike", "occupation": "Python Teacher"}
>>> second_dictionary = {"location": "Iowa", "hobby": "photography"}
>>> first_dictionary.update(second_dictionary)
>>> first_dictionary
{'name': 'Mike', 'occupation': 'Python Teacher', 'location': 'Iowa', 'hobby': 'photography'}

Merging with **

When you use the double-asterisk, it is sometimes called “unpacking”, “expanding” or “splatting” a dictionary.

Here is how you can use ** to merge 2 dictionaries:

>>> first_dictionary = {"name": "Mike", "occupation": "Python Teacher"}
>>> second_dictionary = {"location": "Iowa", "hobby": "photography"}
>>> merged_dictionary = {**first_dictionary, **second_dictionary}
>>> merged_dictionary
{'name': 'Mike', 'occupation': 'Python Teacher', 'location': 'Iowa', 'hobby': 'photography'}

Merging with the Union Operator

Here is how you can use the union operator to merge two dictionaries:

>>> first_dictionary = {"name": "Mike", "occupation": "Python Teacher"} >>> second_dictionary = {"location": "Iowa", "hobby": "photography"}>>> merged_dictionary = first_dictionary | second_dictionary>>> merged_dictionary{'name': 'Mike', 'occupation': 'Python Teacher', 'location': 'Iowa', 'hobby': 'photography'}