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Algorithms & data structures easy

Filter List to Keep Only Whitelist Values in Python

Filter a list of values to keep only those present in a predefined whitelist set using a list comprehension.

filtering sets list-comprehension
Python 
def filter_whitelist(values, whitelist):
    """Return only values that are present in the whitelist set."""
    return [value for value in values if value in whitelist]

if __name__ == "__main__":
    raw_values = ["apple", "banana", "cherry", "date", "apple", "elderberry"]
    allowed = {"apple", "banana", "date"}

…
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