How Do I Count the Occurrences of an Item in a Python List?

How to Count Occurrences of a Specific Item in a List in Python

When you need to determine the number of times a specific item appears within a list in Python, you can use the count method. This method takes the item you want to count as its argument and returns an integer representing the count.

For example:

[1, 2, 3, 4, 1, 4, 1].count(1)

This code will return the value 3, as the item 1 appears three times in the list.

Important Note: It's crucial to be aware that calling count multiple times to count different items in a loop can lead to poor performance. This is because each count call iterates through the entire list of n elements. If you need to count multiple items, consider using the Counter class from the collections module, which only performs n total checks.

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