Consider using the Python built-in function set() inside your lambda function.
# Define the lambda function
remove_duplicates = lambda x: list(set(x))
# Test the function
print(remove_duplicates([5, 3, 8, 5, 3, 9])) # Output: [8, 9, 3, 5]
print(remove_duplicates(['Hello', 'World', 'Hello', 'Python'])) # Output: ['World', 'Python', 'Hello']
NOTEOwing to browser caching, any code input into the Trinket IDE might carry over across page refreshes or when transitioning between different questions. To commence with a clean slate, either click on the 'Reset Button' found within the IDE's Hamburger icon (☰) menu or resort to using Chrome's Incognito Mode.