Python: Create a list with the unique values filtered out

Python List: Exercise - 224 with Solution

Write a Python program to create a list with unique values filtered out.

  • Use collections.Counter to get the count of each value in the list.
  • Use a list comprehension to create a list containing only the non-unique values.

Sample Solution:

Python Code:

from collections import Counter
def filter_unique(lst):
  return [item for item, count in Counter(lst).items() if count > 1] 
print(filter_unique([1, 2, 2, 3, 4, 4, 5]))

Sample Output:

[2, 4]


Flowchart: Create a list with the unique values filtered out.

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Python: Tips of the Day

Given a predicate function, fn, and a prop string, this curried function will then take an object to inspect by calling the property and passing it to the predicate:


def tips_check_prop(fn, prop):
  return lambda obj: fn(obj[prop])
check_age = tips_check_prop(lambda x: x >= 25, 'age')
user = {'name': 'Owen', 'age': 25}





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