Python Dictionary Tutorials
Python – Dictionary example
Basics of a Dictionary
Python – Create a dictionary
Python – Create an empty dictionary
Python – Add item to dictionary
Python – Print dictionary
Python – Dictionary length
Python – Dictionary comprehension
Python - Copy dictionary using Dictionary Comprehension
Access / Traverse Dictionaries
Python – Accessing dictionary
Python – Iterate over dictionary
Python – Loop through key, value in dictionary
Python – Loop through dictionary keys
Python – Loop through dictionary values
Python – Print dictionary keys
Python – Print dictionary values
Update Dictionary
Python – Update dictionary
Python – Merge two dictionaries
Python – Concat dictionary
Python – Delete specific key in dictionary
Python – Remove key based on value in dictionary
Python – Clear or empty a dictionary
Checking Operations on Dictionary
Python – Check if dictionary is empty
Python – Check if dictionary contains specific key
Python – Check if dictionary contains specific value
Conversions to and from Dictionary
Python – Convert dictionary keys to list
Python – Convert dictionary values to list
Python – Convert dictionary to list
Dictionary Methods
Python Dictionary Methods
Python Dictionary clear()
Python Dictionary copy()
Python Dictionary fromkeys()
Python Dictionary get()
Python Dictionary items()
Python Dictionary keys()
Python Dictionary values()
Python Dictionary pop()
Python Dictionary popitem()
Python Dictionary setdefault()
Python Dictionary update()
Dictionary Operations
Python – Sort entries in dictionary based on keys
Python – Sort entries in dictionary based on values
Advanced Topics on Dictionaries
Python – List of dictionaries
Python – Dictionary of lists
Python – Nested dictionary
Python – Write dictionary to file
Python Dictionary Comprehension
Python – Unpack dictionary
Python – Swap keys and values in dictionary
Other Tutorials
Are dictionaries ordered in Python?

Are Dictionaries Ordered in Python?

Dictionaries are ordered

As of Python version 3.7, dictionaries are ordered.

In the previous versions of Python, that is Python 3.6 and earlier, dictionaries are unordered.

Now, what does ordered key-value pairs in a dictionary mean?

It means that the order of keys provided during the creation of a dictionary is preserved.

Consider the following dictionary.

dict1 = {
    "key1": value1,
    "key2": value2,
    "key3": value3,
    "key4": value4}

We have key1 followed by key2 followed by key3 followed by key4. This order of keys is preserved while accessing the key-value pairs of a dictionary.

Suppose we are accessing the key-value pairs in this dictionary using a For loop, then, we would get the key1 first, then key2, then key3, and then key4. Thus the order of given keys is preserved.

If we insert a new key-value "key5":value5, then this would be inserted at the end of the dictionary.

Example

In the following example, we take the above mentioned dictionary, and print the dictionary using print statement. The order of the key-value pairs printed out must be same as that of given in the dictionary. Also, we use a For loop to print out the key-value pairs, the order must be same.

Python Program

dict1 = {
    "key1": 10,
    "key2": 20,
    "key3": 30,
    "key4": 40}

print(dict1)

for key, value in dict1.items():
    print(key, value)

Output

{'key1': 10, 'key2': 20, 'key3': 30, 'key4': 40}
key1 10
key2 20
key3 30
key4 40

Summary

In this tutorial, we learned how dictionaries are ordered in Python, with examples.