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Python Duplicate Removal
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Python Duplicate Removal

EasyPython

Problem

Write a Python program to remove duplicates from a list.

Implement remove_duplicates(items) so it returns a new list containing each value only once, preserving the order of its first occurrence. The input list contains hashable values, and the original list must not be modified.

Function Contract

  • Input: a list of hashable values
  • Output: a new list with duplicates removed

Examples:

  • [3, 1, 3, 2, 1] returns [3, 1, 2].
  • [] returns [].

Constraints: 0 <= len(items) <= 10^4.

Constraints

  • 0 <= len(items) <= 10^4
  • Every item is hashable
  • The original list must not be modified
  • The first occurrence of each value must be preserved

Function Signature

def remove_duplicates(items):
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