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create_list_without_duplicates Function Can be Sped Up By Using Set #794

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@jspeed-meyers

The current implementation of create_list_without_duplicates includes a relatively expensive check of if an element is in a list.

defcreate_list_without_duplicates(list_with_potential_duplicates: List[Any]) ->List[Any]:
list_without_duplicates= []
forelementinlist_with_potential_duplicates:
ifelementnotinlist_without_duplicates:
list_without_duplicates.append(element)
returnlist_without_duplicates

Using a set to keep track of unique elements will speed up this function.

I did a time comparison between this current function and a function that uses a set.

fromtypingimportList, Anyimporttimeit# Original implementationdefcreate_list_without_duplicates_original(list_with_potential_duplicates: List[Any]) ->List[Any]:
list_without_duplicates= []
forelementinlist_with_potential_duplicates:
ifelementnotinlist_without_duplicates:
list_without_duplicates.append(element)
returnlist_without_duplicates# Optimized implementationdefcreate_list_without_duplicates_optimized(list_with_potential_duplicates: List[Any]) ->List[Any]:
seen_elements=set()
list_without_duplicates= []
forelementinlist_with_potential_duplicates:
ifelementnotinseen_elements:
seen_elements.add(element)
list_without_duplicates.append(element)
returnlist_without_duplicates# Test datatest_data=list(range(1000)) *10# Measure time for the original implementationoriginal_time=timeit.timeit(lambda: create_list_without_duplicates_original(test_data), number=1000)
# Measure time for the optimized implementationoptimized_time=timeit.timeit(lambda: create_list_without_duplicates_optimized(test_data), number=1000)
print(f"Original implementation time: {original_time:.1f} seconds")
print(f"Optimized implementation time: {optimized_time:.1f} seconds")

The results are:

Original implementation time: 35.6seconds
Optimized implementation time: 0.2seconds

That original function is about 178x slower. I'll put in a PR for discussion.

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