how to check if there are duplicate values in 2 lists python code example

Example 1: python count repeated elements in a list

# Basic syntax:
dict_of_counts = {item:your_list.count(item) for item in your_list}

# Example usage:
your_list = ["a", "b", "a", "c", "c", "a", "c"]
dict_of_counts = {item:your_list.count(item) for item in your_list}
print(dict_of_counts)
--> {'a': 3, 'b': 1, 'c': 3}

Example 2: check list for duplicate values python

a = [1,2,3,2,1,5,6,5,5,5]

import collections
print([item for item, count in collections.Counter(a).items() if count > 1])

## [1, 2, 5]