Append Dictionary Keys and Values (In order ) in dictionary using Python

When you need to append dictionary keys and values in order, Python provides several approaches. The most straightforward method uses the list() function with .keys() and .values() methods to extract and concatenate them.

Basic Approach Using list() and Concatenation

This method converts dictionary keys and values to lists, then concatenates them ?

my_dict = {"January": 1, "Feb": 2, "March": 3, "April": 4, "May": 5, "June": 6}

print("The dictionary is:")
print(my_dict)

my_result = list(my_dict.keys()) + list(my_dict.values())

print("The ordered key and value are:")
print(my_result)

The dictionary is:
{'January': 1, 'Feb': 2, 'March': 3, 'April': 4, 'May': 5, 'June': 6}
The ordered key and value are:
['January', 'Feb', 'March', 'April', 'May', 'June', 1, 2, 3, 4, 5, 6]

Using List Comprehension

A more Pythonic approach using list comprehension ?

my_dict = {"January": 1, "Feb": 2, "March": 3, "April": 4, "May": 5, "June": 6}

result = [item for pair in zip(my_dict.keys(), my_dict.values()) for item in pair]

print("Interleaved keys and values:")
print(result)

Interleaved keys and values:
['January', 1, 'Feb', 2, 'March', 3, 'April', 4, 'May', 5, 'June', 6]

Using itertools.chain()

For memory-efficient concatenation of multiple iterables ?

import itertools

my_dict = {"January": 1, "Feb": 2, "March": 3, "April": 4, "May": 5, "June": 6}

result = list(itertools.chain(my_dict.keys(), my_dict.values()))

print("Chained keys and values:")
print(result)

Chained keys and values:
['January', 'Feb', 'March', 'April', 4, 'May', 5, 'June', 6]

Comparison

How It Works

• The .keys() method returns a view object containing dictionary keys

• The .values() method returns a view object containing dictionary values

• Converting to list() creates concrete lists from these view objects

• The + operator concatenates the two lists in order

Conclusion

Use simple list concatenation for basic key-value appending. For memory efficiency with large dictionaries, consider itertools.chain(). List comprehension works well when you need interleaved key-value pairs.