Python: Invert a dictionary with unique hashable values

Last update on March 27 2025 12:56:52 (UTC/GMT +8 hours)

72. Invert Dictionary with Unique Values

Write a Python program to invert a dictionary with unique hashable values.

• Use dictionary.items() in combination with a list comprehension to create a new dictionary with the values and keys inverted.

Sample Solution:

Python Code:

# Define a function 'test' that takes a dictionary 'students'.
def test(students):
    # Create a new dictionary where the keys and values from 'students' are swapped.
    # The values become keys, and the keys become values in the new dictionary.
    return {value: key for key, value in students.items()}

# Create a dictionary 'students' with names as keys and corresponding grades as values.
students = {
    'Theodore': 10,
    'Mathew': 11,
    'Roxanne': 9,
}

# Call the 'test' function with the 'students' dictionary to swap keys and values.
print(test(students)) 

Sample Output:

{10: 'Theodore', 11: 'Mathew', 9: 'Roxanne'}

Flowchart:

For more Practice: Solve these Related Problems:

• Write a Python program to invert a dictionary where each value is unique by swapping keys and values.
• Write a Python program to create a new dictionary from a given dictionary with unique values, reversing the mapping using dictionary comprehension.
• Write a Python program to implement a function that returns the inverse of a dictionary with unique hashable values.
• Write a Python program to use the items() method to construct an inverted dictionary from a unique-valued dictionary.

Python Code Editor:

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