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Python program to Convert key-values list to flat dictionary

In this tutorial, we will learn how to write a program that will convert a key-value list to a flat dictionary using the Python programing language. For a given dictionary with pairs of key-value as a list, we have to convert this list to a flat dictionary. A dictionary can be flattened by pairing the same index elements together.

Let us look at the sample input-output of the program.

Input: { "num": [1, 2, 3], "name": ['Monica', 'Joey', 'Jane' ] }

Output: {1: 'Monica', 2: 'Joey', 3: 'Jane'}

To solve this problem in Python, we can use a combination of methods of the dictionary class- zip() and dict(). If you want to know more about dictionary functions in Python.

The zip() method is a built-in function that accepts iterables as parameters and returns a tuple of the elements from each iterable

The dict() method is a built-in function used to create a dictionary in Python.


Follow the algorithm to understand the approach better.

Step 1- Initialise dictionary with key and list values

Step 2- Print original dictionary

Step 3- Declare another dictionary that will store the elements grouped together

Step 4- Use zip() to get the elements in the dictionary in the form of a tuple

Step 5- Use dict() to convert the tuple to a dictionary

Step 6- Print the new dictionary as the result

Python Program

Look at the program to understand the implementation of the above-mentioned approach. We have declared a new dictionary that will be the flattened dictionary and will have the same index elements grouped together.

dic= { "day": [1, 2, 3], "name": ['Mon', 'Tues', 'Wed' ] }
print("Original dictionary: ",dic)

# convert to flat dictionary

f_dic= dict(zip(dic["day"], dic["name"]))
print("FLATTENED DICTIONARY: ", f_dic)

Original dictionary: {'day': [1, 2, 3], 'name': ['Mon', 'Tues', 'Wed']}
FLATTENED DICTIONARY: {1: 'Mon', 2: 'Tues', 3: 'Wed'}


In this tutorial, we have learned what is a flat dictionary and how to convert a pair of key-value where value is a list into a flat dictionary. We have used the zip() method and the dict() method to execute this task.