How to calculate the occurrences of a list item in Python?

Question

Given an item, how to count its occurrences in a list in Python?

Answer 1

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

Answer 2

list.count(x) returns the number of times x appears in a list

see: http://docs.python.org/tutorial/datastructures.html#more-on-lists

Answer 3

I use if x in [] to test for the existence of values, count is meant for another purpose, and for huge lists it's also faster than count. It returns True or False:

Edit: Sorry, I misunderstood your question, my bad.

>>> lst = [1, 2, 3, 4, 5]
>>> 3 in lst
True
>>> 9 in lst
False